Seattle in August

In August, Seattle averages 25°C (76°F) during the day and 15°C (59°F) at night, with around 10 days of rain (27 mm total).

High season

Conditions are comfortable for sightseeing without being sweltering. Plan for unsettled weather and bring rain gear.

It's peak hurricane season in Seattle during August. Travel is possible but expect storm risk, possible flight disruption, and generally lower travel insurance coverage.

25°C
Avg high
15°C
Avg low
10
Rain days
27 mm
Rainfall

How August compares to the rest of the year in Seattle

1st
warmest month of the 12
11th
wettest month of the 12
2%
of yearly rainfall falls in August
14 h 17 min
daylight on the 15th

August is one of the warmest months in Seattle (1st of 12) and one of the driest months (11th of 12). Daytime temperature runs 10°C above the annual average (15°C). August runs roughly the same as July (25°C) and cools 4°C in September (20°C).

August sunrise & sunset in Seattle

🌅
Sunrise (15th)
6:05 AM
🌇
Sunset (15th)
8:22 PM
Day length
14 h 17 min

Times shown for Seattle local time (America/Los_Angeles), calculated for the 15th of August. They shift by a few minutes day to day across the month.

Photography light in Seattle — August

Golden-hour and blue-hour windows for the 15th of August, in Seattle's local time. Use these for soft warm light (golden) or cool architectural twilight (blue).

🌅 Blue hour (AM)
5:05 AM – 5:45 AM
🌄 Golden hour (AM)
5:45 AM – 6:45 AM
🌇 Golden hour (PM)
7:42 PM – 8:42 PM
🌆 Blue hour (PM)
8:42 PM – 9:22 PM
Milky Way galactic core
Fair
Core only briefly above the horizon — a marginal month even from dark sites near Seattle.

📅 When to book — Seattle in August

Travel writers usually only tell you when to go. Here's when to book flights and lodging for the best mix of price and availability, based on August's tier (High season) and Seattle's popularity.

✈ Flights — lead time
3-4 months
Prices are above off-season but not the absolute peak. Tuesday/Wednesday departures are usually cheaper than weekend ones. ⚠ Peak hazard season — book flexible-change tickets and travel insurance with weather-disruption coverage.
🏨 Lodging — lead time
3-5 months
Wide selection still available at this lead time. Premium properties book first; consider 'last-minute deal' availability at 2-week mark if your dates are flexible.

Crowds & pricing — August in Seattle

High season

This is a busy month in Seattle — not the absolute peak, but tourist numbers are clearly elevated. You'll feel it at headline attractions on weekends and in the historic centre, though side streets and lesser-known sights stay manageable. Prices are above off-season but not at their summit. A good week for first-time visitors who want everything open without the worst of the crush.

Why this tier: excellent tourism weather Northern Hemisphere summer holidays peak hazard season (1 active)

Sun & mosquito risk — August in Seattle

☀️ UV Index (noon, 15th)
10.2
Very high
Limit sun exposure between 11 AM and 3 PM; SPF 30-50, reapply every 90 minutes outdoors.
🦟 Mosquito risk
●●●○○
Moderate
Active mosquito season. DEET 25-30% repellent recommended, especially at dawn/dusk.

UV is a clear-sky sea-level estimate — clouds, altitude, and reflective surfaces (snow, water) shift it ±30%. Mosquito risk is climate-derived only; for current disease advisories (dengue, malaria, zika) check the CDC or WHO travel pages before your trip.

Seattle in other months

MonthAvg highAvg lowRainfallRain daysSnow days
January 8°C / 47°F 3°C / 37°F 182 mm 21
February 8°C / 46°F 2°C / 36°F 125 mm 21
March 11°C / 52°F 4°C / 39°F 123 mm 20
April 14°C / 57°F 6°C / 42°F 93 mm 19
May 18°C / 65°F 10°C / 49°F 56 mm 16
June 21°C / 70°F 12°C / 54°F 50 mm 14
July 25°C / 76°F 15°C / 58°F 16 mm 8
August 25°C / 76°F 15°C / 59°F 27 mm 10
September 20°C / 69°F 12°C / 54°F 65 mm 15
October 15°C / 59°F 9°C / 48°F 138 mm 18
November 10°C / 50°F 5°C / 41°F 178 mm 21
December 7°C / 45°F 3°C / 37°F 185 mm 20

Other cities with similar August weather

🌍 See the full ranked list of climate twins for Seattle in August →

Frequently asked questions

How hot is Seattle in August?

In August, Seattle averages a high of 25°C (76°F) and a low of 15°C (59°F) — generally warm.

Does it rain a lot in Seattle in August?

August can be fairly wet in Seattle, with about 10 rainy days on average.

Is August a good time to visit Seattle?

August is warm. It suits travelers who are comfortable with warm weather; check the month-by-month ranking to compare it against the rest of the year.

What should I pack for Seattle in August?

Pack light layers for warm days and cooler evenings, plus a compact umbrella or rain jacket. See the full August packing list for Seattle for a complete, climate-based checklist.

Open Seattle on the interactive map

Check the live 10-day forecast and sunrise/sunset.