| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 3.1° | -7° | 90.7mm | 9.8 | 13 |
| February | 4.7° | -5.7° | 86.1mm | 8.5 | 22 |
| March | 9° | -2° | 104.7mm | 9.1 | 41 |
| April | 15.4° | 3.6° | 130.3mm | 11.5 | 62 |
| May | 21° | 9° | 103.2mm | 11.8 | 76 |
| June | 25.9° | 14.4° | 118.6mm | 11.2 | 78 |
| July | 29° | 17.6° | 101mm | 9.8 | 72 |
| August | 28.2° | 17° | 106.3mm | 9.3 | 77 |
| September | 24.5° | 12.9° | 122.6mm | 9 | 82 |
| October | 17.8° | 6° | 136.3mm | 9.9 | 73 |
| November | 11.6° | 0.8° | 95.1mm | 8.6 | 54 |
| December | 5.9° | -3.8° | 109.9mm | 9.9 | 26 |
January in Hamden averages a daily high of 3.1°C with nights around -7°C. Expect roughly 9.8 wet days totalling 90.7mm. A hard month to visit for comfort alone.
February in Hamden averages a daily high of 4.7°C with nights around -5.7°C. Expect roughly 8.5 wet days totalling 86.1mm. A hard month to visit for comfort alone.
March in Hamden averages a daily high of 9°C with nights around -2°C. Expect roughly 9.1 wet days totalling 104.7mm. Demanding conditions — pack for it and plan indoor options.
April in Hamden averages a daily high of 15.4°C with nights around 3.6°C. Expect roughly 11.5 wet days totalling 130.3mm. Generally workable, with some weather to plan around.
May in Hamden averages a daily high of 21°C with nights around 9°C. Expect roughly 11.8 wet days totalling 103.2mm. Comfortable conditions for being outdoors all day.
June in Hamden averages a daily high of 25.9°C with nights around 14.4°C. Expect roughly 11.2 wet days totalling 118.6mm. Comfortable conditions for being outdoors all day.
July in Hamden averages a daily high of 29°C with nights around 17.6°C. Expect roughly 9.8 wet days totalling 101mm. Generally workable, with some weather to plan around.
August in Hamden averages a daily high of 28.2°C with nights around 17°C. Expect roughly 9.3 wet days totalling 106.3mm. Comfortable conditions for being outdoors all day.
September in Hamden averages a daily high of 24.5°C with nights around 12.9°C. Expect roughly 9 wet days totalling 122.6mm. Comfortable conditions for being outdoors all day.
October in Hamden averages a daily high of 17.8°C with nights around 6°C. Expect roughly 9.9 wet days totalling 136.3mm. Generally workable, with some weather to plan around.
November in Hamden averages a daily high of 11.6°C with nights around 0.8°C. Expect roughly 8.6 wet days totalling 95.1mm. Demanding conditions — pack for it and plan indoor options.
December in Hamden averages a daily high of 5.9°C with nights around -3.8°C. Expect roughly 9.9 wet days totalling 109.9mm. 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. Hamden peaks at 82.
Based on 30 years of records, May–June scores highest for comfort in Hamden, balancing daytime temperature against rainfall.
July is the warmest, averaging a daily high of 29°C.
October is the wettest, averaging 136.3mm of rain across roughly 9.9 wet days.
January is the coolest month, with average daily highs around 3.1°C.