SeasonMapChicago vs Portland: which is better, month by month
Portland beats Chicago in 6 of 12 months — its lead peaks in July (92 vs 76) — while Chicago wins November; they are within 3 points in the other 5 months.
Each place is scored under the lens that suits its type. Comfort is SeasonMap's 0–100 estimate from ERA5 climate normals, not a forecast.
Chicago vs Portland — all 12 months
| Month | Chicago | Portland | Winner | Gap |
|---|---|---|---|---|
| January | 40Ffreezing, a little rain, clean air | 49Fcold, soaked, clean air | Portland | 9 |
| February | 49Ffreezing, a little rain, clean air | 55Dcold, rainy, clean air | Portland | 6 |
| March | 64Ccold, a little rain, clean air | 65Ccool, rainy, clean air | Tie | 1 |
| April | 71Bcool, rainy, clean air | 76Bcool, rainy, clean air | Portland | 5 |
| May | 83Anice, rainy, muggy air | 86Anice, a little rain, clean air | Tie | 3 |
| June | 86Awarm, rainy | 96Swarm, a little rain, clean air | Portland | 10 |
| July | 76Bhot, rainy, muggy air | 92Swarm, dry, clean air | Portland | 16 |
| August | 81Ahot, a little rain | 89Awarm, dry, clean air | Portland | 8 |
| September | 91Swarm, a little rain, clean air | 94Swarm, a little rain, clean air | Tie | 3 |
| October | 73Bnice, rainy, clean air | 72Bnice, rainy, clean air | Tie | 1 |
| November | 62Ccold, a little rain, clean air | 57Dcool, soaked, clean air | Chicago | 5 |
| December | 46Fcold, a little rain, clean air | 45Fcold, soaked, clean air | Tie | 1 |
A month is a tie when the two are within 3 points. The widest gap is July (76 vs 92). Tap a month for that month's temperature, rain, humidity and air quality side by side.