BestRaces| Distances | 5K |
| Surface | road |
| Field size | 216 runners |
| 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 13 in each of the last 5 years, measured at Boonton 1 Se, 4.6 miles from Denville.
| Year | High | Low | Rain |
|---|---|---|---|
| 2026 | 58°F | 29°F | 0.07 in |
| 2025 | 53°F | 34°F | none |
| 2024 | 64°F | 35°F | none |
| 2023 | 45°F | 29°F | 0.04 in |
| 2022 | 42°F | 21°F | 0.25 in |
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 Denville
Hotels and rentals in and around Denville, NJ.
Preset to race weekend, Mar 12 – 14.
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Race Pace Analyzer beta
Build your Coach Mike O'Brien Memorial 5K St. Patrick's Day Run 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
- 5K
- ≈34°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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