Monthly weather averages & travel planning

South America › 🇨🇱 Chile › Santiago
Updated: March 2026
August is a good time to visit Santiago (7/10). With 9 daily sunshine hours and only 8 rain days, this month delivers genuinely reliable outdoor conditions, ranking it 9th sunniest of the year in Santiago. Culture-focused travellers and those who prefer lighter crowds will find August a practical choice, with prices running lower than peak January without sacrificing all the good weather. September offers a similar profile at lower hotel rates if dates are flexible. The main practical note: Santiago's popular sites are busiest between 10am and 3pm regardless of season. Arriving at opening time or after 4pm makes a significant difference to the experience. Planning tips: accommodation is generally available without long lead times, and flight prices are typically lower than peak season. Flexible travellers will find the best deals by booking 2-4 weeks ahead. Mid-week arrivals consistently unlock lower hotel rates than weekend check-ins.
August weather in Santiago is defined by a daily temperature swing from 5°C at night to 16°C during the afternoon. Humidity averages 70%, and you can count on around 9 sunshine hours each day. That combination makes August warm and lush, though dressing in breathable fabrics keeps things manageable.
16°C
61°F
Avg High
5°C
41°F
Avg Low
8 days
79 mm total
Rain Days
9h
per day avg
Sunshine
70%
Moderate
Humidity
The 11°C day-night temperature range is typical for continental climates: a light jacket in the morning that you shed by midday and need again after sunset. Humidity averages 70%, which is comfortable for most visitors. On warmer days, lighter fabrics help with the mild stickiness in the afternoon. The UV index of 2 is low, meaning sun exposure is minimal concern and sunscreen is largely optional. Winds are calm at an average 9 km/h, so wind-chill is not a factor in planning your clothing. In Fahrenheit: 61°F average high, 41°F overnight low. Data sourced from Open-Meteo ERA5 climate reanalysis (1991–2020 normals).
Packing for Santiago in August means dressing for 16°C days and 5°C evenings. A mid-weight jacket over a sweater handles 16°C daytime temperatures; the combination stays comfortable all day without overheating. Evenings drop 11°C to around 5°C, a notable shift that catches underprepared visitors off guard. Pack a dedicated evening layer. Comfortable walking trainers are the versatile choice for both outdoor sightseeing and indoor venues.
Local tip: Layers are more practical than a single heavy garment in Santiago. The day-to-evening temperature shift rewards packing a versatile mid-layer you can add or remove as conditions change.
August has no major festivals or public holidays in Santiago, which is one of its practical advantages for independent travellers. Attractions run at lower capacity than during peak event periods, queues are shorter, and accommodation is easier to find without needing to book many months in advance. Local restaurants, markets, and transport operate at a relaxed pace, making this an ideal time for visitors who prefer a more authentic, unhurried experience of everyday city life rather than large crowds drawn in by a single major headline event.
Based on 16°C average highs and 8 rainy days
August in Santiago reflects a mid-latitude climate pattern, with temperatures averaging 16°C by day and 5°C overnight. The city sits at 33 degrees south latitude, where the balance between solar radiation and heat loss drives conditions that are neither extreme nor static. Conditions occupy the comfortable middle band of the annual temperature range, where outdoor activity is feasible without the extremes of midsummer heat or midwinter cold. Day-to-night temperature variation of 11°C is moderate and manageable with a single mid-layer. Climate data: Open-Meteo ERA5 (1991–2020).
Sunshine Hours
The average number of hours per day with direct sunlight. Calculated from satellite measurements. Days with more than 7 hours of sunshine are ideal for outdoor activities. Under 3 hours means overcast conditions dominate.
UV Index
A scale from 0-11+ measuring ultraviolet radiation intensity. UV 0-2: Minimal risk. UV 3-5: Moderate, wear sunscreen. UV 6-7: High, hat and SPF 30+ essential. UV 8-10: Very High, limit midday exposure. UV 11+: Extreme, seek shade between 10am-4pm.
Rain Days
A rain day is counted when precipitation exceeds 0.1mm. This threshold captures even light drizzle. Unlike total rainfall in mm, rain days tells you how often you might need an umbrella, which is useful for planning outdoor activities.
Humidity
Relative humidity as a percentage. Below 40%: Dry, skin and throat may feel parched. 40-60%: Comfortable, ideal for most people. 60-80%: Sticky, light breathable fabrics recommended. Above 80%: Muggy, heat feels more intense; quick-dry clothing is essential.
Santiago in August
August ranks 9th sunniest of the year in Santiago, with an average 9 daily sunshine hours. The driest months are January, February, and March. January is the hottest month (28°C avg high); June is the coolest (15°C). From here, temperatures rise 2°C into September. Compared to last month (July: 15°C high, 7 rain days), August is warmer and wetter. August sits in the middle of the annual sunshine ranking for Santiago, offering a reasonable balance of good weather and manageable crowds.
| Month | High | Low | Rain Days | Sun | Details |
|---|---|---|---|---|---|
| January | 28°C | 17°C | 1 | 14h | View |
| February | 28°C | 16°C | 1 | 13h | View |
| March | 26°C | 15°C | 1 | 12h | View |
| April | 22°C | 11°C | 3 | 10h | View |
| May | 19°C | 7°C | 6 | 8h | View |
| June | 15°C | 5°C | 7 | 7h | View |
| July | 15°C | 4°C | 7 | 8h | View |
| August | 16°C | 5°C | 8 | 9h | View |
| September | 18°C | 7°C | 8 | 10h | View |
| October | 20°C | 9°C | 6 | 12h | View |
| November | 24°C | 12°C | 3 | 13h | View |
| December | 27°C | 15°C | 1 | 14h | View |
January
1 rain days, 14h sun
February
1 rain days, 13h sun
March
1 rain days, 12h sun
April
3 rain days, 10h sun
May
6 rain days, 8h sun
June
7 rain days, 7h sun
July
7 rain days, 8h sun
August
8 rain days, 9h sun
September
8 rain days, 10h sun
October
6 rain days, 12h sun
November
3 rain days, 13h sun
December
1 rain days, 14h sun
Data Sources for Santiago
Climate normals represent 30-year averages (1991-2020). Individual years may vary.