Windsplit · race guide · Amsterdam, Netherlands
TCS Amsterdam Marathon starts Sunday 18 October 2026 at 09:02 local time from Olympisch Stadion. Below: the live forecast for race day, which parts of the course take the wind, the elevation profile and how to turn it into a pacing plan.
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The out-and-back along the Amstel (roughly km 15–30) is the most exposed part: river, open fields and little shelter.
Numbers are km markers. North is up.
60 m up, 59 m down, -6–6 m above sea level. 10 m between grid lines.
Computed from the direction the course runs in each kilometre. A kilometre counts as headwind when the wind comes from within 60° of straight ahead, and as tailwind when it comes from within 60° of straight behind. Find the forecast wind direction and read your row.
| Wind from | Headwind km | Tailwind km | Headwind share |
|---|---|---|---|
| N (north) | 1–2, 9–10, 21–25, 30–34 | 5–7, 13, 15–19, 27, 41–42 | 34 % |
| NE (north-east) | 1–3, 9–11, 20–22, 24–25, 28–30, 33–34 | 5–7, 13, 15, 18–19, 36–42 | 38 % |
| E (east) | 3–4, 11–12, 16, 25, 28–29 | 6, 19, 23, 31, 35–40 | 19 % |
| SE (south-east) | 4–5, 7, 11–12, 16–18, 27, 29 | 23–24, 31–32, 34–35, 38–39 | 23 % |
| S (south) | 5–7, 13, 15–19, 27, 41–42 | 1–2, 9–10, 21–25, 30–34 | 29 % |
| SW (south-west) | 5–7, 13, 15, 18–19, 36–42 | 1–3, 9–11, 20–22, 24–25, 28–30, 33–34 | 34 % |
| W (west) | 6, 19, 23, 31, 35–40 | 3–4, 11–12, 16, 25, 28–29 | 24 % |
| NW (north-west) | 23–24, 31–32, 34–35, 38–39 | 4–5, 7, 11–12, 16–18, 27, 29 | 19 % |
60 m of climbing and 59 m of descent over 42.195 km, between -6 and 6 m above sea level. The out-and-back along the Amstel (roughly km 15–30) is the most exposed part: river, open fields and little shelter.
It depends on the wind direction on the day. With a wind from the north-east, the course has a headwind on km 1–3, 9–11, 20–22, 24–25, 28–30, 33–34 (38 % of the distance) and a tailwind on km 5–7, 13, 15, 18–19, 36–42. The table on this page lists all eight directions; the race plan uses the actual forecast hour by hour.
Windsplit shows a forecast from 16 days out, but wind forecasts usually converge in the last three days. Check the evening before and again on race morning: the tool refreshes every 30 minutes, and the confidence line shows whether the models agree.
Yes. Replay reads the activity from Strava or a GPX/FIT file, fetches the weather that was recorded along the route, and shows the wind, hill and heat cost per kilometre, plus an adjusted pace in still air. If you planned the race in Windsplit on the same device, it compares the prediction with the result.