| Month | High | Low | Rain | Wet days | Score |
|---|---|---|---|---|---|
| January | 0.1° | -7.9° | 65.4mm | 13.2 | 4 |
| February | 2.3° | -6.1° | 53.5mm | 9.1 | 15 |
| March | 7.7° | -1.2° | 60mm | 10.7 | 34 |
| April | 14.2° | 4.1° | 86.9mm | 11.1 | 59 |
| May | 20.4° | 9.9° | 113.2mm | 12.6 | 75 |
| June | 25.5° | 15.4° | 100.3mm | 11.8 | 76 |
| July | 27.5° | 17.8° | 106.3mm | 9.6 | 79 |
| August | 26.7° | 17.3° | 104.1mm | 9.8 | 80 |
| September | 23.7° | 13.5° | 83.9mm | 9.2 | 82 |
| October | 17.2° | 7.3° | 99.8mm | 11.5 | 68 |
| November | 9.8° | 1.3° | 60.7mm | 9.8 | 47 |
| December | 2.8° | -4.7° | 57.6mm | 12.5 | 10 |
January in Gary averages a daily high of 0.1°C with nights around -7.9°C. Expect roughly 13.2 wet days totalling 65.4mm. A hard month to visit for comfort alone.
February in Gary averages a daily high of 2.3°C with nights around -6.1°C. Expect roughly 9.1 wet days totalling 53.5mm. A hard month to visit for comfort alone.
March in Gary averages a daily high of 7.7°C with nights around -1.2°C. Expect roughly 10.7 wet days totalling 60mm. A hard month to visit for comfort alone.
April in Gary averages a daily high of 14.2°C with nights around 4.1°C. Expect roughly 11.1 wet days totalling 86.9mm. Generally workable, with some weather to plan around.
May in Gary averages a daily high of 20.4°C with nights around 9.9°C. Expect roughly 12.6 wet days totalling 113.2mm. Comfortable conditions for being outdoors all day.
June in Gary averages a daily high of 25.5°C with nights around 15.4°C. Expect roughly 11.8 wet days totalling 100.3mm. Comfortable conditions for being outdoors all day.
July in Gary averages a daily high of 27.5°C with nights around 17.8°C. Expect roughly 9.6 wet days totalling 106.3mm. Comfortable conditions for being outdoors all day.
August in Gary averages a daily high of 26.7°C with nights around 17.3°C. Expect roughly 9.8 wet days totalling 104.1mm. Comfortable conditions for being outdoors all day.
September in Gary averages a daily high of 23.7°C with nights around 13.5°C. Expect roughly 9.2 wet days totalling 83.9mm. Comfortable conditions for being outdoors all day.
October in Gary averages a daily high of 17.2°C with nights around 7.3°C. Expect roughly 11.5 wet days totalling 99.8mm. Generally workable, with some weather to plan around.
November in Gary averages a daily high of 9.8°C with nights around 1.3°C. Expect roughly 9.8 wet days totalling 60.7mm. Demanding conditions — pack for it and plan indoor options.
December in Gary averages a daily high of 2.8°C with nights around -4.7°C. Expect roughly 12.5 wet days totalling 57.6mm. 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. Gary peaks at 82.
Based on 30 years of records, May–September scores highest for comfort in Gary, balancing daytime temperature against rainfall.
July is the warmest, averaging a daily high of 27.5°C.
May is the wettest, averaging 113.2mm of rain across roughly 12.6 wet days.
January is the coolest month, with average daily highs around 0.1°C.