Seattle · AutumnMonth summary
Seattle weather in September
✅ Good
🌡️ Temperature min / max
13°C – 20°C
🌧 Rainy days
31% of days
☀️ Sunshine
10.3h per day on average
🌊 🌊 Season
Autumn
⭐ ⭐ Weather score
7.4/10
📅 📅 Best month
July (9.2/10)
Quick decision
Should you visit Seattle in September?
✅ Good
✅ Yes if: you want to explore the city on foot without suffering from heat.
❌ No if: you're looking for a beach destination — water and air are still cool.
Our take: September is a good time to visit Seattle. July remains slightly better (+1.8 pts).
By trip type
Seattle in September by trip type
- 🏙️ 🏙️ City break / culture : ✅ Good
- 🚶 🚶 Outdoor activities : ⚠️ Possible
- 🏖️ Beach / swimming : ⚠️ Possible
- 💰 💰 Budget : 💸 Peak season
Local context
What to expect in September
🎯 Cultural sites less crowded than peak season — more enjoyable visits Autumn in Seattle is often underrated: 20°C, golden light and declining crowds. An interesting window. Expect rain on 31% of days — a light raincoat in the bag is recommended. Not the best window, but acceptable if dates are constrained. July (9.2/10) is significantly better if possible.
Browse by month
All months for Seattle
Annual table
Month-by-month comparison
| Month | Min °C | Max °C | Rain % | Precip mm | Sun h/d | Score |
|---|---|---|---|---|---|---|
| 🌦️ January | 3°C | 8°C | 58% | 5.7 | 4.3h | 1.7/10 |
| 🌦️ February | 2°C | 8°C | 55% | 4.4 | 5.5h | 2.5/10 |
| 🌦️ March | 4°C | 11°C | 52% | 3.5 | 8.4h | 4.2/10 |
| 🌦️ April | 6°C | 13°C | 47% | 2.8 | 10.4h | 5.3/10 |
| 🌤️ May | 9°C | 18°C | 35% | 1.8 | 11.9h | 7.2/10 |
| 🌤️ June | 12°C | 20°C | 28% | 1.7 | 13.0h | 7.7/10 |
| 🌤️ July | 14°C | 24°C | 11% | 0.4 | 14.5h | 9.2/10 |
| 🌤️ August | 15°C | 24°C | 16% | 0.8 | 12.9h | 8.7/10 |
| 🌤️ September | 13°C | 20°C | 31% | 2.1 | 10.3h | 7.4/10 |
| 🌦️ October | 9°C | 15°C | 45% | 4.0 | 7.5h | 5.0/10 |
| 🌦️ November | 6°C | 10°C | 59% | 5.6 | 4.7h | 2.3/10 |
| 🌦️ December | 3°C | 8°C | 60% | 5.9 | 3.5h | 1.4/10 |
Ideal
Fair
Challenging climate
◀ Current month · Source Open-Meteo · 10 years
📊 Data source
Data based on 10 years of ERA5 records via Open-Meteo, with ECMWF seasonal adjustment. In September, Seattle averages 20°C, 31% rainy days and 10.3h of sunshine per day. Overall weather score: 7.4/10.
See methodology →
Comparison
September vs July (best month)
The best month is July (score 9.2/10). Difference:
- 🌡️ Max temperature : +4°C
- 🌧 Rainy days : -20%
- ☀️ Sunshine : +4.2h/day
FAQ
FAQ — Seattle in September
Is September a good time to visit Seattle?
September is an acceptable time for Seattle (score 7.4/10). Conditions are decent but not optimal — consider July (9.2/10) if possible.
What to do in Seattle in September?
With 20°C max and 10.3h of sunshine, focus on cultural sites, museums and local gastronomy.
Accommodation
Find a place to stay in Seattle
Find places to stay in Seattle in September
Search on Hotels.com
Activities & tours
Activities and tours in Seattle
Guided tours, skip-the-line tickets and local experiences.
Browse activities on GetYourGuide
Flights
Find a flight to Seattle
Compare flights from all airlines.
Search flights
←
Explore also
Similar destinations in September
Vancouver
Yogyakarta🌍 Top destinations
Other top destinations in September
Santiago
Puerto Escondido
Trinidad
Marsa AlamWeather rankings
Compare destinations by weather
Best in EuropeGuides & comparisons