| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | -4.9° | -11.4° | — | — | 24 |
| February | -4.6° | -11.7° | — | — | 24 |
| March | -1° | -8.4° | — | — | 24 |
| April | 4.3° | -2.3° | — | — | 37 |
| May | 11° | 4.5° | — | — | 65 |
| June | 17° | 11° | — | — | 84 |
| July | 20.4° | 14.4° | — | — | 94 |
| August | 18.5° | 12.5° | — | — | 89 |
| September | 13.4° | 8.2° | — | — | 73 |
| October | 6.4° | 2.4° | — | — | 50 |
| November | 1.2° | -2.7° | — | — | 32 |
| December | -2.6° | -7.8° | — | — | 24 |
January in Oulu averages a daily high of -4.9°C with nights around -11.4°C. A hard month to visit for comfort alone.
February in Oulu averages a daily high of -4.6°C with nights around -11.7°C. A hard month to visit for comfort alone.
March in Oulu averages a daily high of -1°C with nights around -8.4°C. A hard month to visit for comfort alone.
April in Oulu averages a daily high of 4.3°C with nights around -2.3°C. Demanding conditions — pack for it and plan indoor options.
May in Oulu averages a daily high of 11°C with nights around 4.5°C. Generally workable, with some weather to plan around.
June in Oulu averages a daily high of 17°C with nights around 11°C. Comfortable conditions for being outdoors all day.
July in Oulu averages a daily high of 20.4°C with nights around 14.4°C. Comfortable conditions for being outdoors all day.
August in Oulu averages a daily high of 18.5°C with nights around 12.5°C. Comfortable conditions for being outdoors all day.
September in Oulu averages a daily high of 13.4°C with nights around 8.2°C. Generally workable, with some weather to plan around.
October in Oulu averages a daily high of 6.4°C with nights around 2.4°C. Demanding conditions — pack for it and plan indoor options.
November in Oulu averages a daily high of 1.2°C with nights around -2.7°C. A hard month to visit for comfort alone.
December in Oulu averages a daily high of -2.6°C with nights around -7.8°C. A hard month to visit for comfort alone.
Each month scores out of 100. It starts at 100 and loses points for daytime highs outside a 20–27°C band, for wet days, and for nights below 2°C. Nothing else is weighted in — no crowd data, no prices, no opinion. Oulu peaks at 94.
Based on 30 years of records, July–August scores highest for comfort in Oulu, balancing daytime temperature against rainfall.
July is the warmest, averaging a daily high of 20.4°C.
January is the wettest, averaging —mm of rain across roughly — wet days.
January is the coolest month, with average daily highs around -4.9°C.