Weather and climate in Tromsø, Troms, Norway
What the weather is like in Tromsø
The warmest month in Tromsø is July, with average highs of 16°C. The coolest is January, when nights average -11°C. About 1,345 mm of rain and snow falls in a typical year, most in September and least in April.
Skies are clearest in July (79% average cloud cover) and cloudiest in December (85%). Combining cloud with the length of truly dark nights, December, January, November offer the most clear, dark hours for stargazing.
Clear, dark hours per night
Hours of full astronomical darkness in mid-month, multiplied by the average share of clear sky. A rough guide to how much good observing time a typical night offers.
Monthly averages
| Month | High | Low | Precipitation | Cloud cover | Humidity | Wind | Dark hours |
|---|---|---|---|---|---|---|---|
| January | -5°C | -11°C | 106 mm | 83% | 96% | 9 km/h | 12.6 h |
| February | -5°C | -10°C | 108 mm | 83% | 95% | 9 km/h | 9.5 h |
| March | -2°C | -8°C | 120 mm | 85% | 93% | 8 km/h | 4.9 h |
| April | 1°C | -4°C | 89 mm | 81% | 92% | 7 km/h | 0.0 h |
| May | 7°C | 1°C | 95 mm | 80% | 85% | 5 km/h | 0.0 h |
| June | 12°C | 6°C | 106 mm | 81% | 81% | 3 km/h | 0.0 h |
| July | 16°C | 9°C | 112 mm | 79% | 81% | 2 km/h | 0.0 h |
| August | 14°C | 8°C | 113 mm | 79% | 85% | 2 km/h | 0.0 h |
| September | 9°C | 4°C | 137 mm | 82% | 90% | 3 km/h | 0.0 h |
| October | 3°C | -1°C | 122 mm | 83% | 95% | 4 km/h | 8.2 h |
| November | -1°C | -6°C | 114 mm | 84% | 96% | 6 km/h | 11.8 h |
| December | -3°C | -8°C | 124 mm | 85% | 96% | 8 km/h | 24.0 h |
Climate averages: NASA POWER, 2001–2025, for the grid area around 69.50, 18.75 (about 50 km across). High and low temperatures are estimated from the monthly mean and the average daily range. Hills, coasts and cities can differ from the area average. Aurora outlook for Tromsø · Sources and methods.