| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 44°F | 70°F | 56°F | 1.6" |
| February | 45°F | 72°F | 57°F | 1.2" |
| March | 47°F | 75°F | 60°F | 0.7" |
| April | 50°F | 78°F | 63°F | 0.5" |
| May | 55°F | 82°F | 66°F | 0.2" |
| June | 59°F | 89°F | 72°F | 0.0" |
| July | 65°F | 94°F | 77°F | 0.2" |
| August | 65°F | 95°F | 78°F | 0.1" |
| September | 63°F | 94°F | 76°F | 0.2" |
| October | 56°F | 85°F | 69°F | 0.2" |
| November | 49°F | 77°F | 62°F | 0.5" |
| December | 44°F | 69°F | 55°F | 1.9" |
| Index | San Gorgonio | San Bernardino | California |
| Air quality index | 89 | 89 | 55 |
| Pollution index | 31,575,300 | 31,575,300 | 10,473,190 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 42 |
| Days with moderate air quality | 178 |
| Days w/ poor A.Q. for sensitive groups | 79 |
| Days with unhealthy air quality | 58 |
| Pollutant | Total |
| Arsenic | 0.110% |
| Benzene | 0.260% |
| Carbon Tetrachloride | 0.020% |
| Lead | 0.350% |
| Mercury | 0.280% |
| City | Population | Air Quality Index | National Avg. |
| Bloomington, CA | 21,907 | 89 | 78.0% |
| Highgrove, CA | 6,201 | 89 | 78.0% |
| Moreno Valley, CA | 208,751 | 89 | 78.0% |
| Crestline, CA | 9,351 | 89 | 78.0% |
| Rialto, CA | 103,549 | 89 | 78.0% |
| San Bernardino, CA | 216,784 | 89 | 78.0% |
| City | Population | Air Quality Index | National Avg. |
| Tacoma, WA | 215,766 | 18 | 64.0% |
| Des Moines, IA | 215,408 | 39 | 22.0% |
| Richmond Hill, ON | 215,407 | n/a | |
| Spring Valley, NV | 218,697 | 54 | 8.0% |
| Enterprise, NV | 214,591 | 54 | 8.0% |
| San Bernardino, CA | 216,784 | 89 | 78.0% |
Here are the best places to live in California
See the best places to live in San Bernardino
These are the 10 cheapest cities in California
Check out the 10 most dangerous cities in California