RAVeL W9 La Véloroute grandeur Nature: which way and when to ride
The best month for RAVeL W9 La Véloroute grandeur Nature is September: 73% of days were dry with highs of 10–30 °C. In September, riding Martelange → Raeren meant an average tailwind of 2.6 km/h (ERA5 2006–2025, daytime 9:00–18:00).
Also passes through Germany
Weather by month
| Month | Good days | Rain days ≥ 1 mm | Rain, mm | Avg high | Days ≥ 30 °C | Days < 10 °C | Daylight, h |
|---|---|---|---|---|---|---|---|
| January | 2% | 33% | 95 | 3 °C | 0% | 96% | 8.5 † |
| February | 8% | 31% | 75 | 5 °C | 0% | 91% | 10.0 † |
| March | 29% | 33% | 81 | 8 °C | 0% | 65% | 11.7 |
| April | 53% | 30% | 62 | 13 °C | 0% | 33% | 13.7 |
| May | 59% | 38% | 89 | 16 °C | 0% | 7% | 15.4 |
| June | 62% | 37% | 101 | 20 °C | 1% | 0% | 16.4 |
| July | 60% | 37% | 96 | 21 °C | 4% | 0% | 16.0 |
| August | 62% | 36% | 98 | 21 °C | 3% | 0% | 14.5 |
| September | 73% | 27% | 77 | 17 °C | 0% | 2% | 12.5 |
| October | 58% | 27% | 81 | 13 °C | 0% | 23% | 10.6 † |
| November | 18% | 33% | 80 | 7 °C | 0% | 75% | 8.9 † |
| December | 3% | 32% | 98 | 4 °C | 0% | 93% | 8.1 † |
Best months are all months within 3 percentage points of the best one. † less than 11 hours of daylight — long stages get tight.
Wind by month
| Month | Wind Raeren → Martelange, km/h | Headwind > 15 km/h, Raeren → Martelange | Headwind > 15 km/h, Martelange → Raeren | Better way |
|---|---|---|---|---|
| January | −6.0 | 24% | 3% | Martelange → Raeren |
| February | −5.3 | 23% | 5% | Martelange → Raeren |
| March | −2.4 | 17% | 7% | Martelange → Raeren |
| April | −0.1 | 11% | 8% | either |
| May | −0.4 | 11% | 7% | either |
| June | −0.6 | 10% | 5% | either |
| July | −2.3 | 12% | 3% | Martelange → Raeren |
| August | −3.3 | 11% | 2% | Martelange → Raeren |
| September | −2.6 | 12% | 4% | Martelange → Raeren |
| October | −5.5 | 21% | 3% | Martelange → Raeren |
| November | −6.9 | 25% | 3% | Martelange → Raeren |
| December | −7.2 | 26% | 3% | Martelange → Raeren |
Along the route (sections of about 25 km)
| km | Heading | Tailwind in September, km/h |
|---|---|---|
| 0–26 | SE | +0.9 |
| 26–51 | S | −3.8 |
| 51–76 | S | −2.3 |
| 76–101 | SW | −4.4 |
| 101–127 | SW | −3.7 |
| 127–155 | S | −2.2 |
How to read the numbers
Wind is the 10 m wind of a 25-km grid cell, daytime hours 9:00–18:00 local solar time; at saddle height in a sheltered valley it is weaker, on a coast or ridge stronger. A positive value is a tailwind. ERA5 slightly over-counts days with ≥ 1 mm of rain (by about 5–7 percentage points) and underestimates daily highs by 1–2 °C. Good day = less than 1 mm of rain between 9:00 and 18:00 (riding hours, local solar time) and a high between 10 and 30 °C; rain at night or in the evening does not spoil it.