18 Hlinsko - České Petrovice: which way and when to ride
The best month for 18 Hlinsko - České Petrovice is September: 74% of days were dry with highs of 10–30 °C. In September the wind barely favours either direction — on average 1.4 km/h along the route (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 | 1% | 25% | 59 | 1 °C | 0% | 98% | 8.5 † |
| February | 5% | 20% | 45 | 3 °C | 0% | 95% | 10.0 † |
| March | 28% | 24% | 53 | 8 °C | 0% | 68% | 11.7 |
| April | 60% | 24% | 49 | 13 °C | 0% | 29% | 13.7 |
| May | 65% | 32% | 80 | 17 °C | 0% | 6% | 15.4 |
| June | 68% | 30% | 85 | 21 °C | 2% | 0% | 16.3 |
| July | 63% | 32% | 90 | 23 °C | 6% | 0% | 15.9 |
| August | 67% | 28% | 95 | 23 °C | 6% | 0% | 14.4 |
| September | 74% | 25% | 80 | 18 °C | 0% | 3% | 12.5 |
| October | 57% | 22% | 55 | 12 °C | 0% | 32% | 10.6 † |
| November | 18% | 21% | 52 | 6 °C | 0% | 79% | 8.9 † |
| December | 1% | 21% | 52 | 2 °C | 0% | 98% | 8.1 † |
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 Hlinsko → Žamberk, km/h | Headwind > 15 km/h, Hlinsko → Žamberk | Headwind > 15 km/h, Žamberk → Hlinsko | Better way |
|---|---|---|---|---|
| January | +4.3 | 1% | 12% | Hlinsko → Žamberk |
| February | +3.1 | 3% | 10% | Hlinsko → Žamberk |
| March | +2.2 | 4% | 9% | Hlinsko → Žamberk |
| April | +0.2 | 5% | 5% | either |
| May | −0.2 | 4% | 4% | either |
| June | +0.4 | 3% | 4% | either |
| July | +2.2 | 1% | 5% | Hlinsko → Žamberk |
| August | +1.9 | 1% | 3% | either |
| September | +1.4 | 2% | 4% | either |
| October | +3.1 | 2% | 7% | Hlinsko → Žamberk |
| November | +4.0 | 1% | 8% | Hlinsko → Žamberk |
| December | +4.6 | 1% | 9% | Hlinsko → Žamberk |
Along the route (sections of about 25 km)
| km | Heading | Tailwind in September, km/h |
|---|---|---|
| 0–25 | NE | +1.1 |
| 25–51 | NE | +1.3 |
| 51–76 | E | +1.8 |
| 76–102 | NE | +1.3 |
| 102–112 | NE | +1.8 |
| 112–114 | NW | −0.6 |
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.