| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 15.3° | 4.3° | 125.9mm | 20.6 | 55 |
| February | 15.1° | 4.2° | 123.8mm | 18.2 | 54 |
| March | 15.4° | 3.3° | 84.1mm | 15.6 | 55 |
| April | 15.6° | 1.1° | 35.9mm | 8.5 | 68 |
| May | 15.4° | -2.6° | 4.3mm | 1.8 | 75 |
| June | 14.6° | -4.1° | 4.5mm | 1.3 | 71 |
| July | 14.5° | -4.4° | 1mm | 0.3 | 72 |
| August | 15.6° | -3.4° | 12.8mm | 3.3 | 71 |
| September | 16.2° | -0.9° | 32.3mm | 6 | 71 |
| October | 17° | 1.2° | 34.5mm | 8 | 73 |
| November | 17.7° | 2.2° | 45.9mm | 11.3 | 70 |
| December | 16.4° | 3.8° | 96.9mm | 17.4 | 58 |
January in Viacha averages a daily high of 15.3°C with nights around 4.3°C. Expect roughly 20.6 wet days totalling 125.9mm. Generally workable, with some weather to plan around.
February in Viacha averages a daily high of 15.1°C with nights around 4.2°C. Expect roughly 18.2 wet days totalling 123.8mm. Demanding conditions — pack for it and plan indoor options.
March in Viacha averages a daily high of 15.4°C with nights around 3.3°C. Expect roughly 15.6 wet days totalling 84.1mm. Generally workable, with some weather to plan around.
April in Viacha averages a daily high of 15.6°C with nights around 1.1°C. Expect roughly 8.5 wet days totalling 35.9mm. Generally workable, with some weather to plan around.
May in Viacha averages a daily high of 15.4°C with nights around -2.6°C. Rain is rare — about 1.8 wet days and 4.3mm across the month. Comfortable conditions for being outdoors all day.
June in Viacha averages a daily high of 14.6°C with nights around -4.1°C. Rain is rare — about 1.3 wet days and 4.5mm across the month. Generally workable, with some weather to plan around.
July in Viacha averages a daily high of 14.5°C with nights around -4.4°C. Rain is rare — about 0.3 wet days and 1mm across the month. Generally workable, with some weather to plan around.
August in Viacha averages a daily high of 15.6°C with nights around -3.4°C. Expect roughly 3.3 wet days totalling 12.8mm. Generally workable, with some weather to plan around.
September in Viacha averages a daily high of 16.2°C with nights around -0.9°C. Expect roughly 6 wet days totalling 32.3mm. Generally workable, with some weather to plan around.
October in Viacha averages a daily high of 17°C with nights around 1.2°C. Expect roughly 8 wet days totalling 34.5mm. Generally workable, with some weather to plan around.
November in Viacha averages a daily high of 17.7°C with nights around 2.2°C. Expect roughly 11.3 wet days totalling 45.9mm. Generally workable, with some weather to plan around.
December in Viacha averages a daily high of 16.4°C with nights around 3.8°C. Expect roughly 17.4 wet days totalling 96.9mm. 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. Viacha peaks at 75.
Based on 30 years of records, April–November scores highest for comfort in Viacha, balancing daytime temperature against rainfall.
November is the warmest, averaging a daily high of 17.7°C.
January is the wettest, averaging 125.9mm of rain across roughly 20.6 wet days.
July is the coolest month, with average daily highs around 14.5°C.