Best time to visit Seattle
Re-score for me — drag the dial — every chart on the page recolours live for your heat limit 27°C
Default 27 °C is the upper edge of the Holiday Climate Index "ideal comfort" band (Scott, Rutty, Amelung & Tang, 2016). Above this, most warm-tourism travellers report measurable discomfort.
How is this scored? HCI / Steadman / CCI gate — full methodology and citations below.
Compare with another destination
Add as many as you like — stacked below the main strips above. Each row is just the recent-window score strip and (for beach destinations) sea-temperature strip.
Tours in Seattle
30 top-rated tours via Viator. Booking links earn this site a commission at no cost to you.
- 1
Best of Mount Rainier National Park from Seattle: All-Inclusive Small-Group Tour - 2
Guided hike on Mt. Rainier - old forest, falls and glacier views - 3
Guided forest hike to Seattle waterfalls incl. Snoqualmie Falls - 4
Chocolate Tour in Seattle with Guided Tastings - 5
Coffee Crawl & VIP Morning in Pike Place Market - 6
Mt. St. Helens National Monument from Seattle: All-Inclusive Small-Group Tour - 7
Pike Place Tour with Vegan and Vegetarian Tastings - 8
Northwest Wine Tasting Tour with Cheese and Chocolate - 9
Downtown Seattle Restaurant Tour with Drinks and Food - 10
Mt. Rainier Day Tour from Seattle - 11
Seattle Coffee Tour: Capitol Hill Coffee Culture & Tastings - 12
Pike Place 90-Minute Tasting Tour - 13
Best of Olympic National Park from Seattle: All-Inclusive Small-Group Day Tour - 14
Seattle Seafood Tour: A Long Lunch of Market-Fresh Tastings - 15
Craft Beer Tasting Tour in Ballard Brewery District with Food - 16
Seattle Airport & Cruise Transfers | SUVs, Vans & Buses - 17
Seattle City and Snoqualmie Falls Half-Day Guided Tour - 18
Seattle City Tour - 19
Chef Guided Food Tour of Pike Place Market - 20
Pike Place Market: Original Food Tour - Tips Included! - 21
Seattle's Sweetest Food Tour: Delicious Donuts, Beignets, & More - 22
Seattle City Highlights Tour - 23
One-Way Seattle Airport Transfer Service - 24
Beneath The Streets Underground History Tour - 25
Seattle's Original Guided Harbor Cruise - 26
Evening Colors Sunset Sail Tour in Seattle - 27
Space Needle and Chihuly Garden and Glass Combination Ticket - 28
Haunted Seattle Booze and Boos Ghost Walking Tour - 29
Seattle Locks Cruise - 30
The Museum of Flight Entrance Ticket
Last refreshed 2026-10-24.
Similar climatesVictoria93% · Vancouver91% · Portland91%
Other destinations with the most-alike year-round climate to Seattle (apparent temperature, rain hours, sunshine — matched within the same trip-profile). The ±N chip compares each match's typical score for the current month against Seattle's. Based on the 2020-2024 climatology, not this year's actual weather.
Month-by-month
| Month | Temp °C | Feels °C | Rain days | Rain h | Rain h/day | Humidity | Wind km/h | Sun h | UV | Interest | Score |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Jan | 3–8 | 5 | 20 | 281 | 14.1 | 82% | 21 | 85 | 1 | Quiet | 2 |
| Feb | 3–8 | 4 | 14 | 203 | 14.5 | 77% | 21 | 105 | 1 | Quiet | 4 |
| Mar | 4–10 | 7 | 14 | 186 | 13.3 | 73% | 20 | 169 | 2 | Quiet | 4 |
| Apr | 5–13 | 10 | 13 | 147 | 11.3 | 65% | 21 | 205 | 4 | Quiet | 6 |
| May | 9–17 | 15 | 12 | 139 | 11.6 | 65% | 19 | 227 | 5 | Moderate | 7 |
| Jun | 12–21 | 19 | 9 | 123 | 13.7 | 62% | 19 | 252 | 6 | Peak | 8 |
| Jul | 15–25 | 24 | 2 | 36 | 18.0 | 54% | 18 | 297 | 7 | Peak | 10 |
| Aug | 15–25 | 24 | 6 | 58 | 9.7 | 57% | 18 | 263 | 6 | Peak | 9 |
| Sep | 13–21 | 20 | 8 | 98 | 12.3 | 64% | 18 | 206 | 4 | Peak | 8 |
| Oct | 9–15 | 13 | 13 | 157 | 12.1 | 74% | 19 | 148 | 2 | Busy | 6 |
| Nov | 5–10 | 7 | 18 | 220 | 12.2 | 79% | 22 | 101 | 1 | Quiet | 3 |
| Dec | 3–8 | 4 | 20 | 249 | 12.4 | 82% | 22 | 78 | 1 | Moderate | 3 |
UV Index in Seattle by Month
UV index in Seattle peaks at 7 (high) in July, dropping to 1 (low) in December. July have high UV — SPF 30+ and sunglasses recommended.
Best months in detail
July
10/1015–25°C · 2 rain days (36h) · 297 sun hours · 54% humidity · Peak crowd · UV 7 (high) · sunniest 1 in 10 days reach 8 (very high)
August
9/1015–25°C · 6 rain days (58h) · 263 sun hours · 57% humidity · Peak crowd · UV 6 (moderate) · sunniest 1 in 10 days reach 8 (high)
September
8/1013–21°C · 8 rain days (98h) · 206 sun hours · 64% humidity · Peak crowd · UV 4 (moderate)
Every month
Show the other 9 months in detail
January
2/103–8°C (feels 5°C) · 20 rain days (281h) · 85 sun hours · 82% humidity · Quiet crowd · UV 1 (low)
February
4/103–8°C (feels 4°C) · 14 rain days (203h) · 105 sun hours · 77% humidity · Quiet crowd · UV 1 (low)
March
4/104–10°C (feels 7°C) · 14 rain days (186h) · 169 sun hours · 73% humidity · Quiet crowd · UV 2 (low) · sunniest 1 in 10 days reach 3 (moderate)
April
6/105–13°C (feels 10°C) · 13 rain days (147h) · 205 sun hours · 65% humidity · Quiet crowd · UV 4 (moderate) · sunniest 1 in 10 days reach 5 (moderate)
May
7/109–17°C (feels 15°C) · 12 rain days (139h) · 227 sun hours · 65% humidity · Moderate crowd · UV 5 (moderate) · sunniest 1 in 10 days reach 7 (high)
June
8/1012–21°C (feels 19°C) · 9 rain days (123h) · 252 sun hours · 62% humidity · Peak crowd · UV 6 (moderate) · sunniest 1 in 10 days reach 8 (high)
October
6/109–15°C (feels 13°C) · 13 rain days (157h) · 148 sun hours · 74% humidity · Busy crowd · UV 2 (low) · sunniest 1 in 10 days reach 4 (moderate)
November
3/105–10°C (feels 7°C) · 18 rain days (220h) · 101 sun hours · 79% humidity · Quiet crowd · UV 1 (low)
December
3/103–8°C (feels 4°C) · 20 rain days (249h) · 78 sun hours · 82% humidity · Moderate crowd · UV 1 (low)
Frequently asked questions about visiting Seattle
When is the best time to visit Seattle?
July is the highest-scoring month (10/10 on the Holiday Climate Index). Typical conditions: 15–25°C (2 rainy days). The top three months by score are July, August, September.
What is the worst time to visit Seattle?
January is the lowest-scoring month (2/10). Typical conditions: 3–8°C (20 rainy days).
When are crowds lowest in Seattle?
Search-interest seasonality (Google Trends 2021-2025) is lowest in January and peaks in August. Interest tracks both in-trip visitors and lead-time planners, so treat it as a "destination is on people's minds" signal rather than literal arrivals.
What is the UV index in Seattle by month?
UV peaks at 7 (high) in July and is lowest in December at 1 (low). Monthly peak values: Jan 1, Feb 1, Mar 2, Apr 4, May 5, Jun 6, Jul 7, Aug 6, Sep 4, Oct 2, Nov 1, Dec 1.
What is the UV index in Seattle in July?
July is the peak UV month in Seattle, with a daily-peak UV index of 7 (high). Apply SPF 30+, wear sunglasses, and seek shade during midday hours.
How high can UV get in Seattle on the sunniest days?
Most days look like the monthly average, but on the sunniest ~1 in 10 days UV climbs higher than the mean suggests. July is the worst case: typical days average UV 7 (high), but the top 10% of days reach UV 8 (very high) — and even higher. Months where the sunniest days routinely exceed the typical reading: March, April, May, June, July, August, October. Plan sun protection for the worst case, not the average.
Is air quality in Seattle bad for travelers?
PM2.5 (fine-particle pollution) exceeds the WHO sensitive-group guideline (15 µg/m³) in 8 months: January, February, March, August, September, October, November, December. The worst month is August with a typical-day mean of 12 µg/m³ (moderate); on the worst 10% of days PM2.5 reaches 20 µg/m³ (unhealthy for sensitive) and higher. People with asthma, heart conditions, or sensitive children may want to avoid these months or limit outdoor activity. Source: CAMS via Open-Meteo.