United States Seattle Weather in August — Climate Guide
August in Seattle is Excellent
Seattle Weather in August — Quick Answer
As of 2026- Avg temp
- 24° / 13°
- Rainfall
- 22mm · 4 days
- Crowds
- Very busy
As of 2026, Seattle in August averages a high of 24°C and low of 13°C with 22mm of rain over about 4 days. Peak summer — same as July. Slight chance of wildfire smoke affecting air quality some years.
August is Excellent for Seattle.
August continues peak July. **Seafair Weekend** (1st weekend) brings hydroplane races on Lake Washington + US Navy Blue Angels jets in the sky. Outdoor concerts run all month. Mt Rainier wildflowers still peak. Watch wildfire smoke days (more common years 2020-2023).
Travel score
Seattle August Weather Stats
Avg High
24°C
Avg Low
13°C
Rainy Days
4
22mm total
Sunshine
9h
Daily avg
Humidity
67%
Comfortable
UV Index
7
High
Wind
12 km/h
Gusts 25
Sea Temp
13°C
Avg water temp
Crowds
Very busy
At attractions
August Sunrise & Sunset
Air Quality
PM2.5
14 μg/m³
PM10
25 μg/m³
Status
Moderate
Feels-Like Temperature & Wind
Feels like
Daytime
24°C
Nighttime
13°C
Humidity and wind affect how the actual temperature feels.
Wind
12 km/h
Max gust 25 km/h
Activities Recommended for August
August Travel Pros & Cons
Pros
- Continued ideal weather (24/13°C)
- Seafair + Blue Angels
- Mt Rainier wildflowers peak
Cons
- Peak hotel rates
- Wildfire smoke possible some years
August Events & Festivals
- Seafair Weekend (Hydroplane Races + Blue Angels)
- Outdoor concert series (Marymoor + Chateau Ste Michelle)
Seattle in August — Full Picture
August continues peak July. **Seafair Weekend** (1st weekend) brings hydroplane races on Lake Washington + US Navy Blue Angels jets in the sky. Outdoor concerts run all month. Mt Rainier wildflowers still peak. Watch wildfire smoke days (more common years 2020-2023).
What to Wear & What to Pack
Peak summer — same as July. Slight chance of wildfire smoke affecting air quality some years.
Packing Checklist
Seasonal Weather Overview
Spring (Mar·Apr·May)
14.3°C
6.7°C
13.3/mo
Summer (Jun·Jul·Aug)
Current22.7°C
12.3°C
5/mo
Autumn (Sep·Oct·Nov)
15.7°C
8°C
13/mo
Winter (Dec·Jan·Feb)
8.7°C
3.3°C
17.3/mo
Seattle Monthly Weather Comparison
| Month | High | Low | Rain | Sun | Humid | UV | Crowd | Price |
|---|---|---|---|---|---|---|---|---|
| 8° | 3° | 18d·145mm | 2h | 80% | 1 | Quiet | Low season | |
| 10° | 4° | 16d·110mm | 3h | 78% | 2 | Quiet | Low season | |
| 12° | 5° | 16d·100mm | 4h | 75% | 3 | Moderate | Shoulder | |
| 14° | 6° | 14d·80mm | 5h | 72% | 4 | Moderate | Shoulder | |
| May (Best) | 17° | 9° | 10d·50mm | 7h | 70% | 6 | Busy | Shoulder |
| June (Best) | 20° | 11° | 8d·38mm | 8h | 68% | 7 | Very busy | Peak |
| July (peak month) (Best) | 24° | 13° | 3d·18mm | 10h | 65% | 8 | Very busy | Peak |
| August (Best) | 24° | 13° | 4d·22mm | 9h | 67% | 7 | Very busy | Peak |
| 21° | 11° | 7d·38mm | 7h | 70% | 5 | Busy | Shoulder | |
| 15° | 8° | 13d·90mm | 4h | 75% | 3 | Moderate | Shoulder | |
| 11° | 5° | 19d·175mm | 2h | 80% | 1 | Quiet | Low season | |
| 8° | 3° | 18d·145mm | 2h | 80% | 1 | Busy | Peak |
View Other Months
Seattle August Hotel Picks
Frequently Asked Questions
Is August a good time to visit Seattle?
Seattle in August is Excellent. Tourist crowds are very busy and flight/hotel prices are peak.
What's the average temperature in Seattle in August?
Seattle August averages a high of 24°C and a low of 13°C.
Does it rain much in Seattle in August?
Seattle August averages 22mm of rainfall over about 4 rainy days.
What should I wear in Seattle in August?
Peak summer — same as July. Slight chance of wildfire smoke affecting air quality some years.
What time are sunrise and sunset in Seattle in August?
Seattle August sunrise is 06:00 and sunset is 20:25, with 14h 25m of daylight.
What's the air quality like in Seattle in August?
Seattle August air quality (AQI) averages 45, rated Good. PM2.5 averages 14μg/m³.
What activities are recommended in Seattle in August?
In August, Seattle is great for Seafair Weekend, Mt Rainier, Outdoor concerts.
Is August peak season in Seattle?
Seattle August crowds are very busy and prices are peak. Advance reservations are strongly recommended.
Best Months to Visit Seattle
View Other Months
Planning a August trip to Seattle?
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Why you can trust weather guide
Based in Chiang Mai for 8+ years, with 30+ countries visited across Southeast Asia, Japan, and Europe. Every detail in this guide is primary-source verified as of April 2026, with prices auto-refreshed via live exchange rate APIs. This isn't AI-generated boilerplate — it's written from the perspective of someone who has actually been there.