BestRacesroad · Half marathon
Brooks Lake Sammamish Half Marathon presented by REI
Build your free race-day pace plan| Distances | Half marathon |
| Surface | road |
| Field size | 2,809 runners |
| Founded | 2010 (16 years) |
| USATF certified | Yes |
| Boston qualifier | No |
From the race's RunSignup listing, with field size from its posted results, last updated September 15, 2026.
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Race-day weather
What the weather did on March 6 in each of the last 5 years, measured at Seattle Sand Pt Wfo, 7.7 miles from Redmond.
| Year | High | Low | Rain |
|---|---|---|---|
| 2026 | 51°F | 44°F | 0.39 in |
| 2025 | 55°F | 38°F | none |
| 2024 | 44°F | 29°F | none |
| 2023 | 51°F | 34°F | none |
| 2022 | 53°F | 34°F | none |
Daily highs and lows, not start-line temperatures: most races start in the cool of the morning, closer to the low. Source: NOAA National Centers for Environmental Information, GHCN-Daily.
Stay near Redmond
Hotels and rentals in and around Redmond, WA.
Preset to race weekend, Mar 5 – 7.
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Race Pace Analyzer beta
Build your Brooks Lake Sammamish Half Marathon presented by REI splits
This one already knows the course. Give it your goal time and it gives you every split to the finish, adjusted for this race's terrain and its usual race-morning temperature, plus a fueling plan and a check on whether the goal fits your fitness. It's free, and there's nothing to sign up for.
- Already loaded
- Half marathon
- ≈42°F on March race mornings
| Mile | Split | Elapsed |
|---|
Training paces for this goal
The everyday paces that build the fitness behind your goal, worked out from your target with the Daniels VDOT model. Save these for your next training block.
Treat these as a guide. Run easy days by feel, and adjust for heat, hills and how your legs feel that day.
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