1 Praha - Brno: which way and when to ride
The best month for 1 Praha - Brno is September: 76% of days were dry with highs of 10–30 °C. In September the wind barely favours either direction — on average 1.6 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 | 3% | 20% | 46 | 2 °C | 0% | 97% | 8.6 † |
| February | 7% | 17% | 36 | 4 °C | 0% | 92% | 10.0 † |
| March | 32% | 22% | 45 | 8 °C | 0% | 64% | 11.7 |
| April | 63% | 23% | 45 | 14 °C | 0% | 25% | 13.7 |
| May | 67% | 31% | 80 | 18 °C | 0% | 4% | 15.3 |
| June | 67% | 30% | 86 | 22 °C | 4% | 0% | 16.3 |
| July | 63% | 29% | 86 | 24 °C | 10% | 0% | 15.9 |
| August | 65% | 27% | 92 | 24 °C | 9% | 0% | 14.4 |
| September | 76% | 22% | 75 | 19 °C | 1% | 2% | 12.5 |
| October | 62% | 20% | 49 | 13 °C | 0% | 26% | 10.6 † |
| November | 21% | 18% | 45 | 7 °C | 0% | 76% | 9.0 † |
| December | 2% | 18% | 43 | 3 °C | 0% | 97% | 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 Praha → Brno, km/h | Headwind > 15 km/h, Praha → Brno | Headwind > 15 km/h, Brno → Praha | Better way |
|---|---|---|---|---|
| January | +3.4 | 5% | 18% | Praha → Brno |
| February | +3.1 | 7% | 17% | Praha → Brno |
| March | +3.1 | 8% | 17% | Praha → Brno |
| April | +2.1 | 7% | 14% | Praha → Brno |
| May | +1.6 | 8% | 12% | either |
| June | +3.1 | 3% | 11% | Praha → Brno |
| July | +4.8 | 2% | 13% | Praha → Brno |
| August | +2.4 | 3% | 7% | Praha → Brno |
| September | +1.6 | 6% | 11% | either |
| October | +0.7 | 8% | 11% | either |
| November | +0.3 | 9% | 12% | either |
| December | +2.2 | 7% | 15% | Praha → Brno |
Along the route (sections of about 25 km)
| km | Heading | Tailwind in September, km/h |
|---|---|---|
| 0–12 | E | +2.2 |
| 12–37 | SE | +2.0 |
| 37–63 | E | +2.0 |
| 63–88 | E | +1.9 |
| 88–113 | E | +1.9 |
| 113–138 | SE | +1.6 |
| 138–163 | E | +1.8 |
| 163–188 | SE | +1.3 |
| 188–213 | SE | +1.5 |
| 213–239 | SE | +1.3 |
| 239–264 | SE | +1.0 |
| 264–277 | SE | +1.0 |
| 277–281 | NW | −1.0 |
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.