Yes
you do need a jacket based on the weather in Hemel Hempstead, UK 1 second ago
Why? Because it's pretty chilly.
51°F10°C & Mostly Cloudy
Wind is 5 mph8 km/h from the N, gusting to 11 mph18 km/h
| May 18 | ||||
| 1am | 51°F10°C | 6 mph9 km/h N | Mostly Cloudy | |
| 2am | 52°F11°C | 6 mph10 km/h N | Cloudy | |
| 3am | 54°F12°C | 7 mph12 km/h N | Cloudy | |
| 4am | 56°F13°C | 8 mph13 km/h N | Cloudy | |
| 5am | 57°F14°C | 8 mph13 km/h N | Cloudy | |
| 6am | 59°F15°C | 8 mph13 km/h N | Cloudy | |
| 7am | 60°F16°C | 8 mph13 km/h N | Mostly Cloudy | |
| 8am | 62°F17°C | 8 mph12 km/h NE | Mostly Cloudy | |
| 9am | 65°F18°C | 8 mph13 km/h NE | Mostly Cloudy | |
| 10am | 66°F19°C | 8 mph13 km/h NE | Mostly Cloudy | |
| 11am | 67°F20°C | 8 mph13 km/h NE | Mostly Cloudy | |
| 12pm | 68°F20°C | 8 mph13 km/h NE | Mostly Cloudy | |
| Date | Low | High | Wind | Day | Night |
|---|---|---|---|---|---|
| May 17 | 51°F10°C | 68°F20°C | 8 mph12 km/h from N | Mostly Cloudy | Partly Cloudy |
| May 18 | 47°F8°C | 70°F21°C | 9 mph15 km/h from NE | Mostly Clear | Mostly Clear |
| May 19 | 46°F8°C | 67°F19°C | 11 mph17 km/h from NE | Partly Cloudy | Mostly Clear |
| May 20 | 44°F7°C | 68°F20°C | 5 mph9 km/h from NE | Partly Cloudy | Drizzle |
| May 21 | 49°F9°C | 67°F19°C | 8 mph13 km/h from NW | Drizzle | Drizzle |
| May 22 | 49°F9°C | 63°F17°C | 13 mph20 km/h from NW | Drizzle | Partly Cloudy |
| May 23 | 47°F8°C | 65°F18°C | 10 mph15 km/h from N | Partly Cloudy | Partly Cloudy |
Yes
Low of 47°F9°C, High of 70°F21°CWind: 9 mph15 km/h
Precipitation: 5% rain