| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | -0.3° | -5° | 41mm | 16 | 5 |
| February | 1.7° | -5.7° | 36.2mm | 13.8 | 6 |
| March | 6.4° | -2.8° | 32.6mm | 12.6 | 24 |
| April | 13.6° | 1.7° | 36.8mm | 10.7 | 58 |
| May | 19.3° | 7.8° | 70.4mm | 12.8 | 72 |
| June | 22.6° | 10.4° | 63.3mm | 12.2 | 76 |
| July | 24.4° | 12.7° | 92.5mm | 14.8 | 70 |
| August | 24° | 12.1° | 71mm | 11.2 | 78 |
| September | 18.5° | 7.3° | 52mm | 10.4 | 74 |
| October | 12.2° | 3.8° | 53.1mm | 12.5 | 50 |
| November | 5.8° | 1.6° | 37mm | 13 | 28 |
| December | 2.2° | — | 53.4mm | 14.8 | 15 |
January in Białystok averages a daily high of -0.3°C with nights around -5°C. Expect roughly 16 wet days totalling 41mm. A hard month to visit for comfort alone.
February in Białystok averages a daily high of 1.7°C with nights around -5.7°C. Expect roughly 13.8 wet days totalling 36.2mm. A hard month to visit for comfort alone.
March in Białystok averages a daily high of 6.4°C with nights around -2.8°C. Expect roughly 12.6 wet days totalling 32.6mm. A hard month to visit for comfort alone.
April in Białystok averages a daily high of 13.6°C with nights around 1.7°C. Expect roughly 10.7 wet days totalling 36.8mm. Generally workable, with some weather to plan around.
May in Białystok averages a daily high of 19.3°C with nights around 7.8°C. Expect roughly 12.8 wet days totalling 70.4mm. Generally workable, with some weather to plan around.
June in Białystok averages a daily high of 22.6°C with nights around 10.4°C. Expect roughly 12.2 wet days totalling 63.3mm. Comfortable conditions for being outdoors all day.
July in Białystok averages a daily high of 24.4°C with nights around 12.7°C. Expect roughly 14.8 wet days totalling 92.5mm. Generally workable, with some weather to plan around.
August in Białystok averages a daily high of 24°C with nights around 12.1°C. Expect roughly 11.2 wet days totalling 71mm. Comfortable conditions for being outdoors all day.
September in Białystok averages a daily high of 18.5°C with nights around 7.3°C. Expect roughly 10.4 wet days totalling 52mm. Generally workable, with some weather to plan around.
October in Białystok averages a daily high of 12.2°C with nights around 3.8°C. Expect roughly 12.5 wet days totalling 53.1mm. Demanding conditions — pack for it and plan indoor options.
November in Białystok averages a daily high of 5.8°C with nights around 1.6°C. Expect roughly 13 wet days totalling 37mm. A hard month to visit for comfort alone.
December in Białystok averages a daily high of 2.2°C. Expect roughly 14.8 wet days totalling 53.4mm. 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. Białystok peaks at 78.
Based on 30 years of records, May–September scores highest for comfort in Białystok, balancing daytime temperature against rainfall.
July is the warmest, averaging a daily high of 24.4°C.
July is the wettest, averaging 92.5mm of rain across roughly 14.8 wet days.
January is the coolest month, with average daily highs around -0.3°C.