Race-day weather · Wyndo for runners
500 Festival Mini-Marathon weather
May 8, 2027 · Indianapolis, IN · traditional start around 7:40 AM (America/Indiana/Indianapolis) — not yet confirmed for 2027. What the start usually feels like, year by year — and a live start-time read once the race confirms its schedule and race week arrives.
Countdown
253 days to race day
The live race-day forecast unlocks 247 days from now, when May 8, 2027 enters the 7-day forecast window. Until then, live hourly data is not available; the history below shows what race morning usually looks like.
The 2027 start time hasn't been published yet — the 7:40 AM start shown here is carried from a previous edition. We'll switch on the live start-time read when the race posts its schedule.
Typical start temp
55°F
median of 11 years
A warm year
57°F
75th percentile start temp
Rain at the start
36%
4 of 11 measured years
Race-morning weather history
Early-May Indianapolis mornings: cool (~45-60°F), spring-shower and occasional-storm risk — typical-climate characterization, UNVERIFIED; ERA5 supplies actuals. 2020 fully CANCELLED (COVID; first cancellation ever). No other cancelled/virtual years found (search not exhaustive). Wyndo tracks what past editions of the race actually served up at the start hour — temperature, dew point, wind, and rain, and reads the live forecast for the start once the race confirms its schedule and race week arrives.
Median start temp
55°F
p75 (a warm year): 57°F
Median dew point
47°F
at the start hour
Rain at the start
36%
4 of 11 measured years
Warmest start
61°F
in 2024
Scroll sideways to see all columns.
| Year | Start temp | Dew point | Wind | Precip (start hr) | Day's high |
|---|---|---|---|---|---|
| 2026 | 37°F | 30°F | 5 mph | dry | 52°F |
| 2025 | 56°F | 54°F | 1 mph | 0.2 mm | 61°F |
| 2024 | 61°F | 59°F | 4 mph | dry | 80°F |
| 2023 | 57°F | 47°F | 6 mph | 0.4 mm | 75°F |
| 2022 | 52°F | 43°F | 13 mph | dry | 66°F |
| 2021 | 37°F | 29°F | 4 mph | dry | 58°F |
| 2019 | 55°F | 53°F | 7 mph | 0.3 mm | 59°F |
| 2018 | 57°F | 51°F | 4 mph | dry | 73°F |
| 2017 | 44°F | 37°F | 9 mph | 1.0 mm | 60°F |
| 2016 | 59°F | 47°F | 10 mph | dry | 76°F |
| 2015 | 54°F | 45°F | 4 mph | dry | 74°F |
Each row is the weather at a real past edition's date and this race's current start hour (ERA5 reanalysis at the start line).
Your heat-adjusted goal for the half marathon
The same cited model as the full calculator, pointed at this race: the median start-hour conditions this calendar slot has served up — climatology, not a forecast.
Your race-day brief
Skip the taper-week refresh spiral. Email briefs for the 500 Festival Mini-Marathon: a race-morning outlook when race day enters the 7-day forecast window, updates only when it changes meaningfully, and a final look the day before.
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Race facts
- Start line
- W Washington Street, downtown Indianapolis (start alongside Military Park / White River State Park). Course heads west to the Speedway, runs one ~2.5-mi lap of the Indianapolis Motor Speedway oval, and returns downtown. Coordinate is an approximate geocode of the W Washington start block.
- Traditional start (not confirmed for 2027)
- 7:40 AM (America/Indiana/Indianapolis) — Headline (Wave 1) gun 7:40 AM; AWD wave 7:35 AM is earlier — a scrape grabbing the last corral (8:40) or "8:00" misses the gun. Source: WTHR 2026 Mini-Marathon timing guide [V]. 2027 waves TBD.
- Field size
- null: no clean half-only finisher count published (2025 results live only on the Xacte JS app). Best-available is ~20,000 PARTICIPANTS (2025, WTHR) — a participant figure, not finishers. The ~30k promo number is the combined Mini+5K; historic peak ~35k (mid-2010s).
- Registration
- open (RunSignup; regularly sells out — 2026 Mini + 5K sold out)
Wyndo is not affiliated with or endorsed by the 500 Festival Mini-Marathon (officially the "IU Health 500 Festival Mini-Marathon") or its organizers. Race names are used descriptively to identify the event; schedules and start times belong to the race — always confirm details on the official site. Weather guidance here is informational, never medical advice, and event alert flags on race day belong to the race's own medical team.