| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 1.5° | -8.8° | 97.6mm | 11.4 | 7 |
| February | 3.4° | -8° | 81.8mm | 8.9 | 14 |
| March | 7.9° | -3.8° | 109.1mm | 10.2 | 32 |
| April | 15.1° | 1.6° | 102.7mm | 11.5 | 61 |
| May | 21.2° | 7.5° | 99.7mm | 12.8 | 74 |
| June | 26.1° | 12.9° | 106.5mm | 11.4 | 77 |
| July | 29.4° | 16.5° | 110.1mm | 10.4 | 70 |
| August | 28.5° | 15.5° | 96.1mm | 9.7 | 75 |
| September | 24.4° | 11.2° | 99.5mm | 8.9 | 82 |
| October | 17.2° | 4.6° | 130.1mm | 10.9 | 69 |
| November | 10.5° | -0.8° | 93.4mm | 10 | 45 |
| December | 4.6° | -5.2° | 114.6mm | 10.8 | 18 |
January in Lowell averages a daily high of 1.5°C with nights around -8.8°C. Expect roughly 11.4 wet days totalling 97.6mm. A hard month to visit for comfort alone.
February in Lowell averages a daily high of 3.4°C with nights around -8°C. Expect roughly 8.9 wet days totalling 81.8mm. A hard month to visit for comfort alone.
March in Lowell averages a daily high of 7.9°C with nights around -3.8°C. Expect roughly 10.2 wet days totalling 109.1mm. A hard month to visit for comfort alone.
April in Lowell averages a daily high of 15.1°C with nights around 1.6°C. Expect roughly 11.5 wet days totalling 102.7mm. Generally workable, with some weather to plan around.
May in Lowell averages a daily high of 21.2°C with nights around 7.5°C. Expect roughly 12.8 wet days totalling 99.7mm. Generally workable, with some weather to plan around.
June in Lowell averages a daily high of 26.1°C with nights around 12.9°C. Expect roughly 11.4 wet days totalling 106.5mm. Comfortable conditions for being outdoors all day.
July in Lowell averages a daily high of 29.4°C with nights around 16.5°C. Expect roughly 10.4 wet days totalling 110.1mm. Generally workable, with some weather to plan around.
August in Lowell averages a daily high of 28.5°C with nights around 15.5°C. Expect roughly 9.7 wet days totalling 96.1mm. Comfortable conditions for being outdoors all day.
September in Lowell averages a daily high of 24.4°C with nights around 11.2°C. Expect roughly 8.9 wet days totalling 99.5mm. Comfortable conditions for being outdoors all day.
October in Lowell averages a daily high of 17.2°C with nights around 4.6°C. Expect roughly 10.9 wet days totalling 130.1mm. Generally workable, with some weather to plan around.
November in Lowell averages a daily high of 10.5°C with nights around -0.8°C. Expect roughly 10 wet days totalling 93.4mm. Demanding conditions — pack for it and plan indoor options.
December in Lowell averages a daily high of 4.6°C with nights around -5.2°C. Expect roughly 10.8 wet days totalling 114.6mm. 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. Lowell peaks at 82.
Based on 30 years of records, May–June scores highest for comfort in Lowell, balancing daytime temperature against rainfall.
July is the warmest, averaging a daily high of 29.4°C.
October is the wettest, averaging 130.1mm of rain across roughly 10.9 wet days.
January is the coolest month, with average daily highs around 1.5°C.