Llanberis Pass – Weather Forecast
Category 3Caernarfon, GB
This page shows a route-based weather forecast for the Llanberis Pass cycling climb in Caernarfon, GB. Unlike a simple location forecast, conditions are calculated at every point along the climb — from the base to the summit — using the actual route profile and elevation data.
You'll see hour-by-hour temperature, wind speed and direction, precipitation probability, and cloud cover adjusted for altitude. Choose your planned departure time to align the forecast with your ride.
Llanberis Pass
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Calculating weather along route...
Trip Summary
Forecast A
Trip Summary A
Forecast B
Trip Summary B
Weather Display Options
Forecast A - Route Map
Forecast B - Route Map
Compare Reversed Route
Same departure time & speed — opposite direction
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← Reversed Direction
Creates a new saved route in the reversed direction
Route Map
Elevation Profile
Temperature Along Route
Precipitation & Precipitation Probability Along Route
Wind Along Route
Humidity Along Route
Pollen Along Route
UV Index Along Route
Start place details
Weather Forecast
Hourly around Mon 31 Aug 00:44
Climate Overview
| Month |
Temp Day
|
Temp Night
|
Sunny Days
|
Sun Hours
|
Rain Days
|
Precipitation
|
Humidity
|
UV Index
|
Day Length
|
|---|---|---|---|---|---|---|---|---|---|
| Jan | 6°C | 1°C | 9 | 3.6h | 23 | 187 mm | 75 % | 2 | 8h 13m |
| Feb | 7°C | 3°C | 14 | 5.4h | 19 | 162 mm | 73 % | 3 | 9h 53m |
| Mar | 11°C | 4°C | 25 | 8.7h | 13 | 55 mm | 70 % | 4 | 11h 54m |
| Apr | 15°C | 7°C | 25 | 9.6h | 15 | 111 mm | 68 % | 5 | 14h 1m |
| May | 16°C | 8°C | 28 | 12.1h | 15 | 105 mm | 65 % | 6 | 15h 52m |
| Jun | 17°C | 12°C | 23 | 9.8h | 24 | 239 mm | 67 % | 7 | 16h 51m |
| Jul | 19°C | 13°C | 26 | 10.8h | 24 | 126 mm | 66 % | 8 | 16h 21m |
| Aug | 19°C | 13°C | 29 | 11.2h | 16 | 102 mm | 68 % | 7 | 14h 41m |
| Sep | 15°C | 10°C | 21 | 7.7h | 26 | 233 mm | 70 % | 5 | 12h 38m |
| Oct | 13°C | 8°C | 17 | 5.4h | 22 | 197 mm | 72 % | 4 | 10h 33m |
| Nov | 10°C | 6°C | 11 | 4.2h | 26 | 290 mm | 76 % | 2 | 8h 40m |
| Dec | 8°C | 5°C | 11 | 4.0h | 20 | 322 mm | 77 % | 2 | 7h 38m |