May 9 is generally a great time to visit Seattle. While there is a slight chance of rain (19%), showers are usually brief. Expect comfortable 17°C weather. Seattle is currently in its most popular travel window, meaning vibrant crowds and premium pricing.
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Essential Travel Info for Seattle
Currency
USD
$ United States dollar
Language
English
Driving
Right side
Connect
The area code for the City of Seattle is...
Safety
Moderate Safety
GPI: 2.44
Seattle Weather Forecast for May 9
"Mild & Comfortable. Expect average highs of 16.5°C. 19% chance of rain."
What to Wear in Seattle in May
Based on historical data for May 9, Seattle typically experiences temperatures between 7.2°C and 16.5°C. We recommend packing light jacket, long pants to stay comfortable. Trends suggest it will stay mostly dry (19% rain probability), but checking the forecast before heading out is always wise.
Complete Packing Guide
Weekly breakdown & essential items for Seattle
Smart Suitcase
- Light Jacket
- Long Pants
Average High
16.5°C
Daytime Peak
Average Low
7.2°C
Nighttime Low
Feels Like
16.5°C
🌤️ Feels accurate
Rain Chance
19%
Avg 1.1mm if it rains
Cloud Cover
59%
Overcast
Pressure
1018.6 hPa
Medium volatility
Seattle Weather Conditions & UV Index
Weather Confidence
30-year variance analysis
Based on 10 years of data
🎯 This date historically delivers consistent weather 80% of the time. Safe to plan outdoor activities with confidence.
Sun Exposure
UV Index & Safety Guide
Protection Needed
SPF 30 recommended
04:00 - 10:00
16:00 - 19:00
Type I-II
🔴 18 min to burn
Type III-IV
🟡 27 min to burn
Type V-VI
🟢 45 min to burn
UV estimate based on latitude, season & cloud cover. Actual UV may vary.
Outdoor Comfort
How pleasant is it outside?
Dew Point
11.4°C
Pleasant
Heat Stress
Low
No heat warning
😊 Best outdoor time:
Any time during daylight hours
Travel & Logistics Insights
Local Calendar
Business Day
Standard hours in United States
Flight Traffic
High
100/100 pressure index
Health Advisory
Healthy
Routine only • View Details →
Landing Slots
~740
Daily arrival options (inc. codeshare)
Sunrise, Sunset & Wind in Seattle
Daylight & Sun
Solar Elevation Cycle
🌅 Sunrise
04:41
☀️ Noon
12:07
🌇 Sunset
19:32
⏱️ Daylight
14h 51m
Wind Speed
13 km/h
Gentle breeze
Sunshine
11.3 hrs
Direct Sun (Cloud-free)
Humidity
72%
Humid / Damp
Travel Intelligence
Exclusive flight analytics & health data for Seattle
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 Seattle
Travel Comfort Index
Real-time tourism conditions
Weather Quality
☀️ Excellent
Tourist Crowds
🟡 Busy
Price Level
💰💰💰 Expensive
Health & Wellbeing
Meteo-Health Forecast
Moderate fluctuations. Some sensitivity possible.
Weather unlikely to affect joint pain.
Moderate fish activity expected.
Air quality is excellent. Perfect for outdoor activities.
Regional Safety Profile
Seismic Activity
Rare minor tremors. Buildings are earthquake-resistant.
Volcanic Activity
Nearest: Mount Rainier
94.3km away
"According to 30YearWeather's analysis of 30 years of NASA satellite data, Seattle on May 9 averages 16.5°C with a 19% precipitation probability. Wedding/Outdoor Event Score: 88/100."
— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology
Seattle Weather History (2010–2024)
Temperature History
Hall of Fame
Records from last 10 years
Better Alternatives Nearby
Consider these dates within ±7 days
May 11
17.3°C • 20% rain
Score
89
May 12
17.7°C • 24% rain
Score
89
May 13
17.9°C • 28% rain
Score
89
💡 Moving your event by a few days could significantly improve weather conditions
Compare Other Cities
Same date (May 9) in other destinations
🌍 Explore the same date in different destinations around the world
📍 Is Seattle Worth Visiting on May 9?
Planning a trip to Seattle on May 9? Our historical weather analysis based on 30 years of NASA satellite data shows that this time of year is characterized by pleasant mild weather averaging 16.5°C with a 19% historical precipitation risk.
✈️ Travel Logistics: Approximately 740 landing slots available daily during this period, indicating peak tourist activity.
📊 Historical Extremes: The hottest May 9 recorded in the last 30 years saw temperatures hit 25.9°C in 2020, while the coldest dropped to 5°C in 2022.