| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 31.3° | 23.6° | 74.1mm | 5.8 | 71 |
| February | 31.7° | 24° | 82.8mm | 6.7 | 68 |
| March | 31.9° | 25.3° | 109.7mm | 10.2 | 60 |
| April | 32.1° | 26° | 285.9mm | 14.9 | 50 |
| May | 31.5° | 26.4° | 317.9mm | 19.8 | 52 |
| June | 30.9° | 26.2° | 176.9mm | 18.4 | 54 |
| July | 30.6° | 25.9° | 102mm | 11.4 | 63 |
| August | 30.5° | 26° | 111.7mm | 12.7 | 61 |
| September | 30.3° | 25.2° | 300.8mm | 18.6 | 57 |
| October | 30.5° | 25° | 322.7mm | 21.2 | 56 |
| November | 30.7° | 24.3° | 361.4mm | 18.8 | 55 |
| December | 30.9° | 23.9° | 252.6mm | 13.8 | 57 |
January in Negombo averages a daily high of 31.3°C with nights around 23.6°C. Expect roughly 5.8 wet days totalling 74.1mm. Generally workable, with some weather to plan around.
February in Negombo averages a daily high of 31.7°C with nights around 24°C. Expect roughly 6.7 wet days totalling 82.8mm. Generally workable, with some weather to plan around.
March in Negombo averages a daily high of 31.9°C with nights around 25.3°C. Expect roughly 10.2 wet days totalling 109.7mm. Generally workable, with some weather to plan around.
April in Negombo averages a daily high of 32.1°C with nights around 26°C. Expect roughly 14.9 wet days totalling 285.9mm. Demanding conditions — pack for it and plan indoor options.
May in Negombo averages a daily high of 31.5°C with nights around 26.4°C. Expect roughly 19.8 wet days totalling 317.9mm. Demanding conditions — pack for it and plan indoor options.
June in Negombo averages a daily high of 30.9°C with nights around 26.2°C. Expect roughly 18.4 wet days totalling 176.9mm. Demanding conditions — pack for it and plan indoor options.
July in Negombo averages a daily high of 30.6°C with nights around 25.9°C. Expect roughly 11.4 wet days totalling 102mm. Generally workable, with some weather to plan around.
August in Negombo averages a daily high of 30.5°C with nights around 26°C. Expect roughly 12.7 wet days totalling 111.7mm. Generally workable, with some weather to plan around.
September in Negombo averages a daily high of 30.3°C with nights around 25.2°C. Expect roughly 18.6 wet days totalling 300.8mm. Generally workable, with some weather to plan around.
October in Negombo averages a daily high of 30.5°C with nights around 25°C. Expect roughly 21.2 wet days totalling 322.7mm. Generally workable, with some weather to plan around.
November in Negombo averages a daily high of 30.7°C with nights around 24.3°C. Expect roughly 18.8 wet days totalling 361.4mm. Generally workable, with some weather to plan around.
December in Negombo averages a daily high of 30.9°C with nights around 23.9°C. Expect roughly 13.8 wet days totalling 252.6mm. Generally workable, with some weather to plan around.
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. Negombo peaks at 71.
Based on 30 years of records, January–February scores highest for comfort in Negombo, balancing daytime temperature against rainfall.
April is the warmest, averaging a daily high of 32.1°C.
November is the wettest, averaging 361.4mm of rain across roughly 18.8 wet days.
September is the coolest month, with average daily highs around 30.3°C.