Nasjonal sykkelrute 9: which way and when to ride
The best month for Nasjonal sykkelrute 9 is September: 69% of days were dry with highs of 10–30 °C. In September, riding near Halden → Innbygda meant an average tailwind of 3.0 km/h (ERA5 2006–2025, daytime 9:00–18:00).
Weather by month
| Month | Good days | Rain days ≥ 1 mm | Rain, mm | Avg high | Days ≥ 30 °C | Days < 10 °C | Daylight, h |
|---|---|---|---|---|---|---|---|
| January | 0% | 21% | 62 | -2 °C | 0% | 100% | 6.6 † |
| February | 0% | 18% | 48 | -1 °C | 0% | 100% | 9.0 † |
| March | 9% | 15% | 41 | 4 °C | 0% | 91% | 11.6 |
| April | 40% | 20% | 44 | 10 °C | 0% | 58% | 14.5 |
| May | 63% | 29% | 75 | 15 °C | 0% | 16% | 17.1 |
| June | 67% | 32% | 88 | 19 °C | 0% | 1% | 18.9 |
| July | 62% | 37% | 113 | 21 °C | 1% | 0% | 18.1 |
| August | 62% | 38% | 113 | 19 °C | 0% | 0% | 15.6 |
| September | 69% | 26% | 80 | 15 °C | 0% | 6% | 12.7 |
| October | 29% | 23% | 77 | 9 °C | 0% | 62% | 9.9 † |
| November | 3% | 23% | 70 | 3 °C | 0% | 95% | 7.3 † |
| December | 0% | 23% | 63 | -1 °C | 0% | 100% | 5.9 † |
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 Halden → Innbygda, km/h | Headwind > 15 km/h, near Halden → Innbygda | Headwind > 15 km/h, Innbygda → near Halden | Better way |
|---|---|---|---|---|
| January | +1.2 | 2% | 8% | either |
| February | +1.7 | 2% | 7% | either |
| March | +1.4 | 3% | 7% | either |
| April | +0.4 | 5% | 5% | either |
| May | +1.5 | 4% | 6% | either |
| June | +2.3 | 3% | 5% | near Halden → Innbygda |
| July | +2.8 | 2% | 4% | near Halden → Innbygda |
| August | +3.3 | 2% | 7% | near Halden → Innbygda |
| September | +3.0 | 2% | 8% | near Halden → Innbygda |
| October | +2.4 | 3% | 8% | near Halden → Innbygda |
| November | +1.6 | 3% | 7% | either |
| December | +1.7 | 2% | 9% | either |
Along the route (sections of about 25 km)
| km | Heading | Tailwind in September, km/h |
|---|---|---|
| 0–25 | E | +2.5 |
| 25–50 | N | +4.0 |
| 50–75 | N | +3.2 |
| 75–100 | NE | +3.7 |
| 100–126 | N | +3.1 |
| 126–151 | NE | +2.9 |
| 151–177 | E | +2.2 |
| 177–202 | N | +3.4 |
| 202–227 | N | +3.1 |
| 227–252 | N | +3.0 |
| 252–278 | N | +3.0 |
| 278–303 | NW | +2.3 |
| 303–328 | N | +3.0 |
| 328–353 | NW | +1.5 |
| 353–379 | N | +3.5 |
| 379–391 | NE | +3.2 |
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.