2: Pärnu - Tallinn: which way and when to ride
The best month for 2: Pärnu - Tallinn is September: 70% of days were dry with highs of 10–30 °C. In September, riding Pärnu → Tallinn meant an average tailwind of 2.2 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% | 20% | 50 | -2 °C | 0% | 100% | 6.9 † |
| February | 0% | 18% | 39 | -2 °C | 0% | 100% | 9.2 † |
| March | 5% | 17% | 36 | 3 °C | 0% | 95% | 11.6 |
| April | 36% | 21% | 40 | 9 °C | 0% | 61% | 14.4 |
| May | 69% | 23% | 49 | 15 °C | 0% | 14% | 16.9 |
| June | 68% | 31% | 75 | 19 °C | 1% | 1% | 18.4 |
| July | 64% | 35% | 80 | 22 °C | 2% | 0% | 17.8 |
| August | 64% | 35% | 94 | 21 °C | 1% | 0% | 15.4 |
| September | 70% | 26% | 62 | 16 °C | 0% | 5% | 12.7 |
| October | 35% | 27% | 66 | 9 °C | 0% | 52% | 10.1 † |
| November | 4% | 21% | 53 | 4 °C | 0% | 95% | 7.6 † |
| December | 0% | 22% | 52 | 1 °C | 0% | 100% | 6.2 † |
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 Pärnu → Tallinn, km/h | Headwind > 15 km/h, Pärnu → Tallinn | Headwind > 15 km/h, Tallinn → Pärnu | Better way |
|---|---|---|---|---|
| January | +3.1 | 7% | 17% | Pärnu → Tallinn |
| February | +2.6 | 6% | 13% | Pärnu → Tallinn |
| March | +1.6 | 9% | 14% | either |
| April | +0.3 | 10% | 12% | either |
| May | +0.4 | 8% | 10% | either |
| June | +0.9 | 9% | 11% | either |
| July | +1.0 | 7% | 10% | either |
| August | +2.3 | 6% | 12% | Pärnu → Tallinn |
| September | +2.2 | 8% | 14% | Pärnu → Tallinn |
| October | +3.0 | 8% | 17% | Pärnu → Tallinn |
| November | +3.7 | 7% | 16% | Pärnu → Tallinn |
| December | +3.9 | 7% | 19% | Pärnu → Tallinn |
Along the route (sections of about 25 km)
| km | Heading | Tailwind in September, km/h |
|---|---|---|
| 0–25 | NE | +4.7 |
| 25–51 | NE | +4.8 |
| 51–77 | NE | +4.7 |
| 77–93 | NE | +4.5 |
| 93–118 | NE | +4.4 |
| 118–143 | N | +3.4 |
| 143–168 | N | +2.9 |
| 168–197 | NW | −2.0 |
| 197–222 | W | −3.0 |
| 222–234 | W | −4.5 |
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.