| 2023 Hardiness Zone: | Zone 10b: 35°F to 40°F Zone 10a: 30°F to 35°F | |
| 2012 Hardiness Zone: | Zone 10a: 30°F to 35°F | |
| 1990 Hardiness Zone: | Zone 10a: 30F to 35F | |
| Average First Frost Date: | No Frost | |
| Average Last Frost Date: | Frost Rare | |
| Koppen-Geiger Climate Zone: | Csa - Hot-Summer Mediterranean Climate | |
| Ecoregion: | ||
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | 61 - 90 days Over 86°F |
Annual Climate Data for ZIP Code 91748 - Rowland Heights, CA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 42 | 44 | 45 | 48 | 52 | 56 | 60 | 60 | 59 | 53 | 46 | 42 | 51 |
| Avg Max Temp (°F) | 68 | 70 | 70 | 75 | 77 | 83 | 89 | 90 | 88 | 82 | 74 | 69 | 78 |
| Avg Precip (In.) | 3.81 | 3.79 | 3.14 | .85 | .33 | .11 | .01 | .22 | .32 | .52 | 1.31 | 2.12 | 16.54 |