| 2023 Hardiness Zone: | Zone 10b: 35°F to 40°F | |
| 2012 Hardiness Zone: | Zone 9b: 25°F to 30°F Zone 10a: 30°F to 35°F | |
| 1990 Hardiness Zone: | Zone 10a: 30F to 35F | |
| Average First Frost Date: | Jan. 1 - Jan. 10 | |
| Average Last Frost Date: | Jan. 21 - Jan. 31 | |
| Koppen-Geiger Climate Zone: | Csb - Warm-Summer Mediterranean Climate | |
| Ecoregion: | ||
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | 1 - 7 days Over 86°F |
Annual Climate Data for ZIP Code 91941 - La Mesa, CA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 44 | 46 | 48 | 51 | 55 | 59 | 62 | 64 | 62 | 56 | 48 | 43 | 53 |
| Avg Max Temp (°F) | 68 | 69 | 71 | 73 | 74 | 79 | 84 | 86 | 84 | 79 | 73 | 68 | 76 |
| Avg Precip (In.) | 2.87 | 2.54 | 2.93 | 1.02 | .33 | .11 | .05 | .1 | .29 | .56 | 1.31 | 1.54 | 13.67 |