August 25 is statistically one of the best days of the year in Siena. With minimal rain risk (11%) and pleasant highs of 30°C, it's ideal for outdoor adventures. As it's peak season for Siena, we recommend booking your stay well in advance to secure the best rates.
View the full calendar
Essential Travel Info for Siena
Currency
EUR
€ Euro
Language
Italian
+1 more
Driving
Right side
Safety
High Safety
GPI: 1.643
Siena Weather Forecast for August 25
"Warm & Sunny. Expect average highs of 29.8°C. 11% chance of rain."
What to Wear in Siena in August
Based on historical data for August 25, Siena typically experiences temperatures between 17.8°C and 29.8°C. We recommend packing t-shirt, light clothing, layers (onion system) to stay comfortable. Trends suggest it will stay mostly dry (11% rain probability), but checking the forecast before heading out is always wise.
Complete Packing Guide
Weekly breakdown & essential items for Siena
Smart Suitcase
- T-Shirt
- Light Clothing
- Layers (Onion System)
Average High
29.8°C
Daytime Peak
Average Low
17.8°C
Nighttime Low
Feels Like
33°C
🔥 Feels warmer
Rain Chance
11%
Avg 0.7mm if it rains
Cloud Cover
31%
Overcast
Pressure
1014.3 hPa
Low volatility
Siena Weather Conditions & UV Index
Weather Confidence
30-year variance analysis
Based on 10 years of data
🎯 This date historically delivers consistent weather 97% of the time. Safe to plan outdoor activities with confidence.
Sun Exposure
UV Index & Safety Guide
Protection Needed
SPF 30 recommended
05:00 - 10:00
16:00 - 19:00
Type I-II
🔴 15 min to burn
Type III-IV
🟡 23 min to burn
Type V-VI
🟢 38 min to burn
UV estimate based on latitude, season & cloud cover. Actual UV may vary.
Outdoor Comfort
How pleasant is it outside?
Dew Point
22°C
Humid/Sticky
Heat Index
33°C
Feels hotter
🙂 Best outdoor time:
Any time during daylight hours
Travel & Logistics Insights
Local Calendar
Business Day
Standard hours in Italy
Flight Traffic
High
100/100 pressure index
Health Advisory
Required
1 vaccine • View Details →
Landing Slots
~64
Daily arrival options (inc. codeshare)
Sunrise, Sunset & Wind in Siena
Daylight & Sun
Solar Elevation Cycle
🌅 Sunrise
05:32
☀️ Noon
12:18
🌇 Sunset
19:04
⏱️ Daylight
13h 32m
Wind Speed
12.5 km/h
Gentle breeze
Sunshine
11.9 hrs
Direct Sun (Cloud-free)
Humidity
63%
Slightly humid
Travel Intelligence
Exclusive flight analytics & health data for Siena
Smart Flight Estimator
Airport-to-Airport Logistics
unlock smart flight estimates
Add your home location in settings to see airport details.
Travel Health & Safety in Siena
Travel Comfort Index
Real-time tourism conditions
Weather Quality
☀️ Excellent
Tourist Crowds
🔴 Very Busy
Price Level
💰💰💰 Expensive
Health & Wellbeing
Meteo-Health Forecast
Stable conditions. Low risk of headaches.
Weather unlikely to affect joint pain.
Moderate fish activity expected.
Air quality is acceptable. Sensitive individuals should limit prolonged outdoor exertion.
Regional Safety Profile
Seismic Activity
Moderate seismic activity. Occasional tremors possible.
"According to 30YearWeather's analysis of 30 years of NASA satellite data, Siena on August 25 averages 29.8°C with a 11% precipitation probability. Wedding/Outdoor Event Score: 100/100."
— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology
Siena Weather History (2010–2024)
Temperature History
Hall of Fame
Records from last 10 years
Compare Other Cities
Same date (August 25) in other destinations
🌍 Explore the same date in different destinations around the world
📍 Is Siena Worth Visiting on August 25?
Planning a trip to Siena on August 25? Our historical weather analysis based on 30 years of NASA satellite data shows that this time of year typically offers vibrant summer conditions averaging 29.8°C with a 11% historical precipitation risk.
✈️ Travel Logistics: Approximately 64 landing slots available daily during this period, indicating manageable crowd levels.
💉 Health Advisory: 7 vaccinations are recommended for Italy, including COVID-19.
📊 Historical Extremes: The hottest August 25 recorded in the last 30 years saw temperatures hit 36.5°C in 2023, while the coldest dropped to 15.2°C in 2016.