Véloroute du Nord, stage 4: Cergy-Pontoise → Paris
On stage 4 (Cergy-Pontoise → Paris, 70 km) the best month is September: 81% 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).
← Véloroute du Nord (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 | 15% | 23% | 60 | 7 °C | 0% | 76% | 8.7 † |
| February | 29% | 23% | 52 | 8 °C | 0% | 60% | 10.1 † |
| March | 53% | 26% | 57 | 12 °C | 0% | 33% | 11.7 |
| April | 72% | 24% | 46 | 16 °C | 0% | 7% | 13.6 |
| May | 71% | 28% | 66 | 19 °C | 0% | 1% | 15.3 |
| June | 72% | 23% | 64 | 22 °C | 5% | 0% | 16.2 |
| July | 72% | 18% | 52 | 25 °C | 11% | 0% | 15.8 |
| August | 73% | 19% | 56 | 24 °C | 9% | 0% | 14.4 |
| September | 81% | 17% | 44 | 21 °C | 2% | 0% | 12.5 |
| October | 77% | 21% | 69 | 16 °C | 0% | 3% | 10.7 † |
| November | 47% | 22% | 62 | 11 °C | 0% | 38% | 9.1 † |
| December | 21% | 23% | 71 | 8 °C | 0% | 67% | 8.2 † |
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 Cergy-Pontoise → Paris, km/h | Headwind > 15 km/h, Cergy-Pontoise → Paris | Headwind > 15 km/h, Paris → Cergy-Pontoise | Better way |
|---|---|---|---|---|
| January | +0.1 | 8% | 8% | either |
| February | +0.3 | 8% | 9% | either |
| March | +1.1 | 7% | 10% | either |
| April | +1.1 | 5% | 7% | either |
| May | +2.6 | 3% | 9% | Cergy-Pontoise → Paris |
| June | +2.1 | 2% | 5% | Cergy-Pontoise → Paris |
| July | +2.8 | 2% | 7% | Cergy-Pontoise → Paris |
| August | +2.4 | 2% | 6% | Cergy-Pontoise → Paris |
| September | +1.1 | 3% | 6% | either |
| October | −0.9 | 7% | 5% | either |
| November | −1.1 | 9% | 7% | either |
| December | −0.7 | 9% | 7% | either |
Along the route (sections of about 25 km)
| km | Heading | Tailwind in September, km/h |
|---|---|---|
| 370–396 | S | +0.4 |
| 396–419 | E | +2.4 |
| 419–441 | S | +0.6 |
Other stages
- Halluin → Dainville 80 km
- Dainville → Beauvais 120 km
- Beauvais → Cergy-Pontoise 124 km
- Cergy-Pontoise → Paris 70 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.