Route des Grandes Alpes à vélo - Tracé principal, stage 2: Beaufort → Modane
On stage 2 (Beaufort → Modane, 151 km) the best month is August: 57% of days were dry with highs of 10–30 °C; the wind barely favours either direction (1.1 km/h on average; ERA5 2006–2025, 9:00–18:00).
← Route des Grandes Alpes à vélo - Tracé principal (Whole route)
Weather by month
| Month | Good days | Rain days ≥ 1 mm | Rain, mm | Avg high | Days ≥ 30 °C | Days < 10 °C | Daylight, h |
|---|---|---|---|---|---|---|---|
| January | 0% | 27% | 122 | -4 °C | 0% | 100% | 9.1 † |
| February | 1% | 26% | 87 | -2 °C | 0% | 99% | 10.3 † |
| March | 4% | 31% | 123 | 1 °C | 0% | 96% | 11.8 |
| April | 13% | 36% | 111 | 5 °C | 0% | 84% | 13.5 |
| May | 24% | 51% | 156 | 9 °C | 0% | 58% | 14.9 |
| June | 39% | 57% | 136 | 15 °C | 0% | 14% | 15.7 |
| July | 53% | 46% | 122 | 17 °C | 0% | 3% | 15.3 |
| August | 57% | 42% | 114 | 17 °C | 0% | 5% | 14.1 |
| September | 54% | 38% | 99 | 13 °C | 0% | 22% | 12.5 |
| October | 36% | 26% | 99 | 9 °C | 0% | 60% | 10.8 † |
| November | 5% | 29% | 140 | 2 °C | 0% | 95% | 9.4 † |
| December | 0% | 29% | 145 | -3 °C | 0% | 100% | 8.7 † |
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 Beaufort → Modane, km/h | Headwind > 15 km/h, Beaufort → Modane | Headwind > 15 km/h, Modane → Beaufort | Better way |
|---|---|---|---|---|
| January | −0.4 | 0% | 0% | either |
| February | +0.1 | 0% | 0% | either |
| March | +0.5 | 0% | 0% | either |
| April | +0.5 | 0% | 0% | either |
| May | +0.8 | 0% | 0% | either |
| June | +0.9 | 0% | 0% | either |
| July | +1.2 | 0% | 0% | either |
| August | +1.1 | 0% | 0% | either |
| September | +0.8 | 0% | 0% | either |
| October | +0.1 | 0% | 0% | either |
| November | −0.3 | 0% | 0% | either |
| December | −0.5 | 0% | 0% | either |
Along the route (sections of about 25 km)
| km | Heading | Tailwind in August, km/h |
|---|---|---|
| 128–153 | SE | +3.8 |
| 153–178 | SE | +4.6 |
| 178–203 | SE | +1.1 |
| 203–228 | SE | +1.1 |
| 228–254 | SW | −1.1 |
| 254–279 | SW | −2.8 |
Other stages
- Thonon-les-Bains → Beaufort 128 km
- Beaufort → Modane 151 km
- Modane → Guillestre 134 km
- Guillestre → Péone 116 km
- Péone → Nice 168 km
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.