| 2023 Hardiness Zone: | Zone 5a: -20°F to -15°F Zone 4b: -25°F to -20°F Zone 5b: -15°F to -10°F |
| 2012 Hardiness Zone: | Zone 5a: -20°F to -15°F Zone 4b: -25°F to -20°F Zone 5b: -15°F to -10°F |
| 1990 Hardiness Zone: | Zone 1b: -15F to -10F |
| Average First Frost Date: | Sep.1 - Sep. 10 |
| Average Last Frost Date: | Jun. 11 - Jun. 20 |
| Koppen-Geiger Climate Zone: | BSk - Cold Semi-Arid Climate |
| Ecoregion: | 18c - Wet Valleys |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 82937 - Lyman, WY | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 12 | 14 | 20 | 27 | 35 | 43 | 49 | 48 | 40 | 31 | 20 | 13 | 29 |
| Avg Max Temp (°F) | 32 | 36 | 44 | 53 | 64 | 74 | 81 | 80 | 71 | 59 | 43 | 34 | 56 |
| Avg Precip (In.) | .47 | .32 | .55 | .86 | 1.1 | .76 | .56 | .65 | .8 | .63 | .51 | .39 | 7.6 |