Nasjonal sykkelrute 4, stage 4: near Lærdalsøyri → Ål
On stage 4 (near Lærdalsøyri → Ål, 155 km) the best month is June: 49% of days were dry with highs of 10–30 °C; the wind barely favours either direction (1.6 km/h on average; ERA5 2006–2025, 9:00–18:00).
← Nasjonal sykkelrute 4 (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% | 32% | 97 | -5 °C | 0% | 100% | 6.4 † |
| February | 0% | 26% | 70 | -4 °C | 0% | 100% | 8.9 † |
| March | 0% | 29% | 77 | -2 °C | 0% | 100% | 11.6 |
| April | 4% | 27% | 61 | 3 °C | 0% | 96% | 14.6 |
| May | 24% | 33% | 80 | 7 °C | 0% | 72% | 17.3 |
| June | 49% | 41% | 112 | 13 °C | 0% | 29% | 19.2 |
| July | 46% | 51% | 139 | 15 °C | 0% | 11% | 18.4 |
| August | 48% | 48% | 138 | 13 °C | 0% | 15% | 15.8 |
| September | 31% | 38% | 123 | 10 °C | 0% | 58% | 12.8 |
| October | 2% | 36% | 116 | 4 °C | 0% | 98% | 9.9 † |
| November | 0% | 32% | 102 | -1 °C | 0% | 100% | 7.2 † |
| December | 0% | 34% | 108 | -4 °C | 0% | 100% | 5.6 † |
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 near Lærdalsøyri → Ål, km/h | Headwind > 15 km/h, near Lærdalsøyri → Ål | Headwind > 15 km/h, Ål → near Lærdalsøyri | Better way |
|---|---|---|---|---|
| January | +0.4 | 1% | 2% | either |
| February | +0.3 | 0% | 1% | either |
| March | +1.0 | 1% | 2% | either |
| April | +1.4 | 1% | 4% | either |
| May | +1.1 | 1% | 2% | either |
| June | +1.6 | 1% | 3% | either |
| July | +0.6 | 1% | 2% | either |
| August | −0.1 | 1% | 1% | either |
| September | +0.3 | 1% | 2% | either |
| October | 0.0 | 1% | 1% | either |
| November | +0.1 | 0% | 2% | either |
| December | +0.5 | 1% | 1% | either |
Along the route (sections of about 25 km)
| km | Heading | Tailwind in June, km/h |
|---|---|---|
| 385–410 | NE | +2.5 |
| 410–435 | E | +3.3 |
| 435–461 | E | +2.9 |
| 461–487 | SE | +1.8 |
| 487–512 | S | −1.8 |
| 512–540 | SE | +0.8 |
Other stages
- Asker → Flå 135 km
- Flå → Geilo 115 km
- Geilo → near Lærdalsøyri 136 km
- near Lærdalsøyri → Ål 155 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.