Yes
you do need a jacket based on the weather in Ontario, CA, USA 1 second ago
Why? Because it's not very warm out!
54°F12°C & Cloudy
Wind is 2 mph3 km/h from the West, gusting to 4 mph6 km/h
| May 1 | ||||
| 10am | 55°F13°C | 2 mph3 km/h Northwest | Cloudy | |
| 11am | 56°F13°C | 1 mph2 km/h Southwest | Cloudy | |
| 12pm | 58°F14°C | 2 mph3 km/h South | Cloudy | |
| 1pm | 61°F16°C | 2 mph4 km/h Southwest | Partly Cloudy | |
| 2pm | 66°F19°C | 4 mph6 km/h Southwest | Mostly Clear | |
| 3pm | 70°F21°C | 5 mph8 km/h Southwest | Mostly Clear | |
| 4pm | 72°F22°C | 7 mph11 km/h Southwest | Mostly Clear | |
| 5pm | 74°F23°C | 8 mph13 km/h Southwest | Mostly Clear | |
| 6pm | 74°F24°C | 9 mph15 km/h Southwest | Partly Cloudy | |
| 7pm | 74°F23°C | 10 mph16 km/h Southwest | Partly Cloudy | |
| 8pm | 72°F22°C | 11 mph17 km/h West | Partly Cloudy | |
| 9pm | 70°F21°C | 10 mph16 km/h West | Partly Cloudy | |
| Date | Low | High | Wind | Day | Night |
|---|---|---|---|---|---|
| May 1 | 53°F12°C | 74°F24°C | 6 mph10 km/h from Southwest | Partly Cloudy | Mostly Clear |
| May 2 | 53°F12°C | 78°F25°C | 6 mph10 km/h from Southwest | Mostly Clear | Mostly Clear |
| May 3 | 54°F12°C | 71°F22°C | 7 mph11 km/h from Southwest | Partly Cloudy | Mostly Cloudy |
| May 4 | 51°F10°C | 59°F15°C | 5 mph8 km/h from South | Drizzle | Cloudy |
| May 5 | 51°F11°C | 61°F16°C | 5 mph7 km/h from Southwest | Cloudy | Drizzle |
| May 6 | 51°F11°C | 69°F21°C | 6 mph9 km/h from Southwest | Mostly Clear | Clear |
| May 7 | 55°F13°C | 77°F25°C | 6 mph9 km/h from Southwest | Clear | Clear |
Yes
Low of 53°F12°C, High of 78°F26°CWind: 6 mph10 km/h
Precipitation: None