| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 0.5° | -7.4° | 34.9mm | 13.9 | 3 |
| February | 2.5° | -4.4° | 29.7mm | 12.4 | 11 |
| March | 7° | -2.5° | 26.1mm | 10.6 | 30 |
| April | 14.1° | 2.9° | 38.1mm | 10.8 | 60 |
| May | 19.5° | 8° | 65.7mm | 12.9 | 73 |
| June | 23° | 11.2° | 74.5mm | 12.8 | 74 |
| July | 25.1° | 12.7° | 71.2mm | 12.8 | 74 |
| August | 24.6° | 11.8° | 69.3mm | 11.6 | 77 |
| September | 19.1° | 8.3° | 48.1mm | 10 | 77 |
| October | 13° | 4° | 40.2mm | 10.4 | 57 |
| November | 6.4° | -0.1° | 31.8mm | 11.4 | 31 |
| December | 1.8° | -4.6° | 35.3mm | 13.2 | 9 |
January in Siedlce averages a daily high of 0.5°C with nights around -7.4°C. Expect roughly 13.9 wet days totalling 34.9mm. A hard month to visit for comfort alone.
February in Siedlce averages a daily high of 2.5°C with nights around -4.4°C. Expect roughly 12.4 wet days totalling 29.7mm. A hard month to visit for comfort alone.
March in Siedlce averages a daily high of 7°C with nights around -2.5°C. Expect roughly 10.6 wet days totalling 26.1mm. A hard month to visit for comfort alone.
April in Siedlce averages a daily high of 14.1°C with nights around 2.9°C. Expect roughly 10.8 wet days totalling 38.1mm. Generally workable, with some weather to plan around.
May in Siedlce averages a daily high of 19.5°C with nights around 8°C. Expect roughly 12.9 wet days totalling 65.7mm. Generally workable, with some weather to plan around.
June in Siedlce averages a daily high of 23°C with nights around 11.2°C. Expect roughly 12.8 wet days totalling 74.5mm. Generally workable, with some weather to plan around.
July in Siedlce averages a daily high of 25.1°C with nights around 12.7°C. Expect roughly 12.8 wet days totalling 71.2mm. Generally workable, with some weather to plan around.
August in Siedlce averages a daily high of 24.6°C with nights around 11.8°C. Expect roughly 11.6 wet days totalling 69.3mm. Comfortable conditions for being outdoors all day.
September in Siedlce averages a daily high of 19.1°C with nights around 8.3°C. Expect roughly 10 wet days totalling 48.1mm. Comfortable conditions for being outdoors all day.
October in Siedlce averages a daily high of 13°C with nights around 4°C. Expect roughly 10.4 wet days totalling 40.2mm. Generally workable, with some weather to plan around.
November in Siedlce averages a daily high of 6.4°C with nights around -0.1°C. Expect roughly 11.4 wet days totalling 31.8mm. A hard month to visit for comfort alone.
December in Siedlce averages a daily high of 1.8°C with nights around -4.6°C. Expect roughly 13.2 wet days totalling 35.3mm. 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. Siedlce peaks at 77.
Based on 30 years of records, May–September scores highest for comfort in Siedlce, balancing daytime temperature against rainfall.
July is the warmest, averaging a daily high of 25.1°C.
June is the wettest, averaging 74.5mm of rain across roughly 12.8 wet days.
January is the coolest month, with average daily highs around 0.5°C.