Weather
Climate Avg| Time | Temp | Dew Pt | Humidity | Wind | Conditions |
|---|---|---|---|---|---|
| Start | 32.3 – 41.2°F | 34° Crisp | 79 – 96% | 5 mph NE | Partly cloudy |
| 8:00 AM | 32.4 – 40.9°F | 34° Crisp | 78 – 95% | 5 mph E | Partly cloudy |
| Finish | 40.7 – 40.7°F | 33° Crisp | 75 – 75% | 7 mph NE | Partly cloudy |
Based on 3-year average for this date. Real forecast available in 75 days.
Elevation Profile
Course Stats
Mile Splits
| Mile | Grade |
|---|---|
| 1 | -0.9% |
| 2 | +1.1% |
| 3 | -0.7% |
| 4 | -0.7% |
| 5 | -2.1% |
| 6 | +2.2% |
| 7 | -2.8% |
| 8 | +1.0% |
| 9 | -0.1% |
| 10 | -0.3% |
| 11 | +1.9% |
| 12 | -1.2% |
| 13 | -0.8% |
| 14 | +5.1% |
RM Difficulty Index
Race-Day Weather History
Race-morning conditions on this date over the past 6 years: median 37°F with a 33°F dew point and 5 mph wind. Heat has rarely been a factor.
| Year | Temp | Dew Pt | Wind | Rain | Sky |
|---|---|---|---|---|---|
| 2024 | 39°F | 36°F | 5 mph | — | Partly cloudy |
| 2023 | 33°F | 32°F | 3 mph | — | Partly cloudy |
| 2022 | 34°F | 27°F | 6 mph | — | Snow |
| 2021 | 53°F | 51°F | 10 mph | — | Drizzle |
| 2020 | 39°F | 34°F | 2 mph | — | Partly cloudy |
| 2019 | 31°F | 23°F | 5 mph | — | Clear |
Morning conditions (race window) on the Seattle Half Marathon calendar date each year, from the ERA5 reanalysis archive — the race’s usual slot, not necessarily each edition’s exact day.
Seattle Half Marathon Pace Calculator & Race Plan
The Seattle Half starts at the Space Needle, heads south through downtown, then runs north on the I-5 express lanes before crossing to the University of Washington campus. About 500 feet of gain from the rolling terrain.
Late November in Seattle means cool, likely wet conditions. Our model adjusts for the hills and the Pacific Northwest weather.
Seattle Half Marathon FAQ
When is the next Seattle Half Marathon?›
The next Seattle Half Marathon is on Sunday, November 29, 2026.
How long is the Seattle Half Marathon?›
The Seattle Half Marathon is 13.1 miles (21.097 km), the standard half marathon distance. It runs in Seattle, WA.
How much elevation gain does the Seattle Half Marathon have?›
The Seattle Half Marathon has about 1,129 ft (344 m) of climbing and 1,285 ft of descent, with a maximum grade of 20.1%.
Is the Seattle Half Marathon flat, downhill, or hilly?›
The Seattle Half Marathon is a net downhill course, dropping 157 ft (48 m) from start to finish, with 1,129 ft of climbing along the way.
How hard is the Seattle Half Marathon?›
Runner's Math scores the Seattle Half Marathon 57/100 (Challenging) — #4 of 16 half marathons in our library, ranked by modeled time cost. The profile costs about 1:41 versus a flat course for a runner at 4:00-marathon pace.
What's the weather usually like at the Seattle Half Marathon?›
Over the past 6 years on this date, median race-morning conditions were 37°F with a 33°F dew point and 5 mph wind. Heat has rarely been a factor.