Weather information for the North Cascades NP area is provided below. Average temperatures, climate details and current forecasts are included.
Climate
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
| Avg. High | 44 | 47 | 51 | 55 | 61 | 66 | 70 | 71 | 66 | 58 | 48 | 44 |
| Avg. Low | 31 | 34 | 36 | 40 | 45 | 50 | 54 | 54 | 48 | 42 | 37 | 32 |
| Avg. Precip. | 4.7 | 3.6 | 3.0 | 2.7 | 2.3 | 1.8 | 1.3 | 1.4 | 1.9 | 3.4 | 5.0 | 5.0 |

