| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 10.7° | 6.1° | 20.5mm | 8.7 | 53 |
| February | 13.8° | 8.2° | 20.2mm | 7.3 | 66 |
| March | 19.1° | 11.3° | 51.4mm | 10.9 | 75 |
| April | 24° | 15.7° | 99.3mm | 13.8 | 72 |
| May | 27.7° | 19.4° | 142.5mm | 15.2 | 67 |
| June | 29.8° | 22.2° | 209.6mm | 15.6 | 59 |
| July | 33.9° | 25.2° | 191.9mm | 11.5 | 49 |
| August | 34.3° | 25° | 115.2mm | 9.3 | 52 |
| September | 29.7° | 21.6° | 121.2mm | 11.5 | 66 |
| October | 22.4° | 16.9° | 88.9mm | 14.8 | 70 |
| November | 17.5° | 12.4° | 50.3mm | 10.3 | 71 |
| December | 11.8° | 7.8° | 23.7mm | 8.3 | 57 |
January in Bishan averages a daily high of 10.7°C with nights around 6.1°C. Expect roughly 8.7 wet days totalling 20.5mm. Demanding conditions — pack for it and plan indoor options.
February in Bishan averages a daily high of 13.8°C with nights around 8.2°C. Expect roughly 7.3 wet days totalling 20.2mm. Generally workable, with some weather to plan around.
March in Bishan averages a daily high of 19.1°C with nights around 11.3°C. Expect roughly 10.9 wet days totalling 51.4mm. Comfortable conditions for being outdoors all day.
April in Bishan averages a daily high of 24°C with nights around 15.7°C. Expect roughly 13.8 wet days totalling 99.3mm. Generally workable, with some weather to plan around.
May in Bishan averages a daily high of 27.7°C with nights around 19.4°C. Expect roughly 15.2 wet days totalling 142.5mm. Generally workable, with some weather to plan around.
June in Bishan averages a daily high of 29.8°C with nights around 22.2°C. Expect roughly 15.6 wet days totalling 209.6mm. Generally workable, with some weather to plan around.
July in Bishan averages a daily high of 33.9°C with nights around 25.2°C. Expect roughly 11.5 wet days totalling 191.9mm. Demanding conditions — pack for it and plan indoor options.
August in Bishan averages a daily high of 34.3°C with nights around 25°C. Expect roughly 9.3 wet days totalling 115.2mm. Demanding conditions — pack for it and plan indoor options.
September in Bishan averages a daily high of 29.7°C with nights around 21.6°C. Expect roughly 11.5 wet days totalling 121.2mm. Generally workable, with some weather to plan around.
October in Bishan averages a daily high of 22.4°C with nights around 16.9°C. Expect roughly 14.8 wet days totalling 88.9mm. Generally workable, with some weather to plan around.
November in Bishan averages a daily high of 17.5°C with nights around 12.4°C. Expect roughly 10.3 wet days totalling 50.3mm. Generally workable, with some weather to plan around.
December in Bishan averages a daily high of 11.8°C with nights around 7.8°C. Expect roughly 8.3 wet days totalling 23.7mm. 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. Bishan peaks at 75.
Based on 30 years of records, March–May scores highest for comfort in Bishan, balancing daytime temperature against rainfall.
August is the warmest, averaging a daily high of 34.3°C.
June is the wettest, averaging 209.6mm of rain across roughly 15.6 wet days.
January is the coolest month, with average daily highs around 10.7°C.