| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 1.1° | -14.3° | 2.4mm | 2.2 | 26 |
| February | 5.1° | -10.5° | 8.8mm | 4.8 | 28 |
| March | 11.8° | -2.7° | 7.1mm | 3.6 | 60 |
| April | 17.3° | 1.5° | 29.7mm | 7.2 | 76 |
| May | 21.9° | 6.3° | 52.7mm | 10 | 80 |
| June | 25.5° | 10.4° | 38.7mm | 8.8 | 82 |
| July | 27.4° | 12.3° | 85.1mm | 11.8 | 75 |
| August | 26.3° | 12.2° | 93.2mm | 11.2 | 78 |
| September | 20.3° | 8.2° | 70.4mm | 13 | 74 |
| October | 14.9° | 1.5° | 27.3mm | 8.3 | 66 |
| November | 8.5° | -6.9° | 4.7mm | 2.4 | 45 |
| December | 2.1° | -13.3° | 1.8mm | 1.7 | 27 |
January in Lanzhou averages a daily high of 1.1°C with nights around -14.3°C. Rain is rare — about 2.2 wet days and 2.4mm across the month. A hard month to visit for comfort alone.
February in Lanzhou averages a daily high of 5.1°C with nights around -10.5°C. Expect roughly 4.8 wet days totalling 8.8mm. A hard month to visit for comfort alone.
March in Lanzhou averages a daily high of 11.8°C with nights around -2.7°C. Expect roughly 3.6 wet days totalling 7.1mm. Generally workable, with some weather to plan around.
April in Lanzhou averages a daily high of 17.3°C with nights around 1.5°C. Expect roughly 7.2 wet days totalling 29.7mm. Comfortable conditions for being outdoors all day.
May in Lanzhou averages a daily high of 21.9°C with nights around 6.3°C. Expect roughly 10 wet days totalling 52.7mm. Comfortable conditions for being outdoors all day.
June in Lanzhou averages a daily high of 25.5°C with nights around 10.4°C. Expect roughly 8.8 wet days totalling 38.7mm. Comfortable conditions for being outdoors all day.
July in Lanzhou averages a daily high of 27.4°C with nights around 12.3°C. Expect roughly 11.8 wet days totalling 85.1mm. Comfortable conditions for being outdoors all day.
August in Lanzhou averages a daily high of 26.3°C with nights around 12.2°C. Expect roughly 11.2 wet days totalling 93.2mm. Comfortable conditions for being outdoors all day.
September in Lanzhou averages a daily high of 20.3°C with nights around 8.2°C. Expect roughly 13 wet days totalling 70.4mm. Generally workable, with some weather to plan around.
October in Lanzhou averages a daily high of 14.9°C with nights around 1.5°C. Expect roughly 8.3 wet days totalling 27.3mm. Generally workable, with some weather to plan around.
November in Lanzhou averages a daily high of 8.5°C with nights around -6.9°C. Rain is rare — about 2.4 wet days and 4.7mm across the month. Demanding conditions — pack for it and plan indoor options.
December in Lanzhou averages a daily high of 2.1°C with nights around -13.3°C. Rain is rare — about 1.7 wet days and 1.8mm across the month. 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. Lanzhou peaks at 82.
Based on 30 years of records, April–September scores highest for comfort in Lanzhou, balancing daytime temperature against rainfall.
July is the warmest, averaging a daily high of 27.4°C.
August is the wettest, averaging 93.2mm of rain across roughly 11.2 wet days.
January is the coolest month, with average daily highs around 1.1°C.