No
you don't need a jacket based on the weather in Ontario, CA, USA 1 second ago
65°F18°C & Clear
Wind is 6 mph9 km/h from the W, gusting to 13 mph21 km/h
| September 21 | ||||
| 12am | 64°F18°C | 4 mph6 km/h W | Clear | |
| 1am | 63°F17°C | 2 mph4 km/h W | Clear | |
| 2am | 62°F17°C | 2 mph3 km/h NW | Clear | |
| 3am | 61°F16°C | 2 mph4 km/h N | Mostly Clear | |
| 4am | 60°F16°C | 2 mph3 km/h NE | Mostly Clear | |
| 5am | 60°F15°C | 2 mph3 km/h NE | Mostly Clear | |
| 6am | 59°F15°C | 1 mph2 km/h NE | Mostly Clear | |
| 7am | 58°F15°C | 2 mph4 km/h NE | Mostly Clear | |
| 8am | 58°F14°C | 3 mph4 km/h N | Mostly Clear | |
| 9am | 57°F14°C | 2 mph4 km/h NE | Partly Cloudy | |
| 10am | 57°F14°C | 2 mph3 km/h NE | Partly Cloudy | |
| 11am | 59°F15°C | 1 mph2 km/h E | Partly Cloudy | |
| Date | Low | High | Wind | Day | Night |
|---|---|---|---|---|---|
| September 20 | 60°F15°C | 74°F23°C | 5 mph8 km/h from W | Partly Cloudy | Mostly Clear |
| September 21 | 57°F14°C | 79°F26°C | 5 mph8 km/h from SW | Mostly Clear | Clear |
| September 22 | 61°F16°C | 88°F31°C | 5 mph9 km/h from W | Clear | Clear |
| September 23 | 65°F18°C | 91°F33°C | 6 mph10 km/h from W | Clear | Clear |
| September 24 | 65°F18°C | 89°F32°C | 6 mph10 km/h from W | Clear | Clear |
| September 25 | 65°F18°C | 87°F31°C | 6 mph10 km/h from W | Clear | Clear |
| September 26 | 65°F18°C | 87°F31°C | 6 mph10 km/h from W | Mostly Clear | Mostly Clear |
Yes
Low of 57°F14°C, High of 80°F27°CWind: 5 mph8 km/h
Precipitation: None