| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 4.7° | -1.9° | 25.2mm | 12.2 | 21 |
| February | 8.4° | -1.4° | 16.5mm | 8.3 | 41 |
| March | 13.9° | 1.8° | 15.7mm | 8 | 64 |
| April | 18.2° | 4.9° | 13.8mm | 6.5 | 81 |
| May | 23.1° | 9.2° | 15mm | 7.2 | 86 |
| June | 27.1° | 12.8° | 12.4mm | 4.5 | 91 |
| July | 32.4° | 16° | 3.6mm | 1.7 | 75 |
| August | 31.6° | 15.6° | 2.9mm | 1.9 | 78 |
| September | 26.1° | 11.2° | 7.1mm | 3.3 | 93 |
| October | 18° | 5.7° | 14.6mm | 7 | 80 |
| November | 9.5° | 0.9° | 22.3mm | 10.4 | 44 |
| December | 4.2° | -2.2° | 30.1mm | 12.7 | 18 |
January in Richland averages a daily high of 4.7°C with nights around -1.9°C. Expect roughly 12.2 wet days totalling 25.2mm. A hard month to visit for comfort alone.
February in Richland averages a daily high of 8.4°C with nights around -1.4°C. Expect roughly 8.3 wet days totalling 16.5mm. Demanding conditions — pack for it and plan indoor options.
March in Richland averages a daily high of 13.9°C with nights around 1.8°C. Expect roughly 8 wet days totalling 15.7mm. Generally workable, with some weather to plan around.
April in Richland averages a daily high of 18.2°C with nights around 4.9°C. Expect roughly 6.5 wet days totalling 13.8mm. Comfortable conditions for being outdoors all day.
May in Richland averages a daily high of 23.1°C with nights around 9.2°C. Expect roughly 7.2 wet days totalling 15mm. Comfortable conditions for being outdoors all day.
June in Richland averages a daily high of 27.1°C with nights around 12.8°C. Expect roughly 4.5 wet days totalling 12.4mm. Comfortable conditions for being outdoors all day.
July in Richland averages a daily high of 32.4°C with nights around 16°C. Rain is rare — about 1.7 wet days and 3.6mm across the month. Comfortable conditions for being outdoors all day.
August in Richland averages a daily high of 31.6°C with nights around 15.6°C. Rain is rare — about 1.9 wet days and 2.9mm across the month. Comfortable conditions for being outdoors all day.
September in Richland averages a daily high of 26.1°C with nights around 11.2°C. Expect roughly 3.3 wet days totalling 7.1mm. Comfortable conditions for being outdoors all day.
October in Richland averages a daily high of 18°C with nights around 5.7°C. Expect roughly 7 wet days totalling 14.6mm. Comfortable conditions for being outdoors all day.
November in Richland averages a daily high of 9.5°C with nights around 0.9°C. Expect roughly 10.4 wet days totalling 22.3mm. Demanding conditions — pack for it and plan indoor options.
December in Richland averages a daily high of 4.2°C with nights around -2.2°C. Expect roughly 12.7 wet days totalling 30.1mm. 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. Richland peaks at 93.
Based on 30 years of records, May–June scores highest for comfort in Richland, balancing daytime temperature against rainfall.
July is the warmest, averaging a daily high of 32.4°C.
December is the wettest, averaging 30.1mm of rain across roughly 12.7 wet days.
December is the coolest month, with average daily highs around 4.2°C.