LF Zuiderzeeroute: clockwise or anticlockwise, and when to ride
The best month for LF Zuiderzeeroute is September: 76% of days were dry in riding hours with highs of 10–30 °C. In September the wind barely favours either way round — under 2 km/h on average (ERA5 2006–2025, daytime 9:00–18:00).
This route is a loop: the two directions are clockwise and anticlockwise.
Weather by month
| Month | Good days | Rain days ≥ 1 mm | Rain, mm | Avg high | Days ≥ 30 °C | Days < 10 °C | Daylight, h |
|---|---|---|---|---|---|---|---|
| January | 4% | 26% | 70 | 6 °C | 0% | 90% | 8.1 † |
| February | 10% | 25% | 59 | 6 °C | 0% | 86% | 9.8 † |
| March | 32% | 21% | 53 | 9 °C | 0% | 62% | 11.7 |
| April | 59% | 20% | 44 | 13 °C | 0% | 28% | 13.9 |
| May | 72% | 25% | 64 | 16 °C | 0% | 4% | 15.8 |
| June | 75% | 24% | 68 | 19 °C | 1% | 0% | 16.8 |
| July | 66% | 31% | 91 | 21 °C | 3% | 0% | 16.4 |
| August | 68% | 30% | 88 | 21 °C | 2% | 0% | 14.7 |
| September | 76% | 23% | 70 | 18 °C | 0% | 0% | 12.6 |
| October | 69% | 26% | 82 | 14 °C | 0% | 6% | 10.5 † |
| November | 33% | 27% | 69 | 10 °C | 0% | 52% | 8.6 † |
| December | 9% | 25% | 74 | 7 °C | 0% | 83% | 7.7 † |
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, clockwise, km/h | Headwind > 15 km/h, clockwise | Headwind > 15 km/h, anticlockwise | Better way |
|---|---|---|---|---|
| January | −0.3 | 20% | 18% | either |
| February | −0.3 | 19% | 18% | either |
| March | 0.0 | 17% | 17% | either |
| April | +0.2 | 15% | 15% | either |
| May | +0.2 | 15% | 15% | either |
| June | +0.3 | 13% | 14% | either |
| July | +0.2 | 13% | 14% | either |
| August | 0.0 | 13% | 14% | either |
| September | 0.0 | 14% | 14% | either |
| October | −0.3 | 17% | 17% | either |
| November | −0.4 | 19% | 17% | either |
| December | −0.4 | 20% | 18% | either |
Along the route (sections of about 25 km)
| km | Heading | Tailwind in September, km/h |
|---|---|---|
| 0–26 | NE | +4.3 |
| 26–51 | N | +1.9 |
| 51–76 | NE | +6.2 |
| 76–101 | NW | −3.3 |
| 101–128 | N | +2.3 |
| 128–153 | NE | +7.1 |
| 153–178 | S | −2.0 |
| 178–204 | SE | +2.7 |
| 204–230 | E | +4.7 |
| 230–255 | SE | +1.8 |
| 255–281 | SW | −5.2 |
| 281–306 | S | −1.9 |
| 306–331 | S | −3.1 |
| 331–356 | SW | −4.8 |
| 356–381 | SW | −4.8 |
| 381–406 | NW | −2.6 |
| 406–435 | W | −3.4 |
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.