Yes
you do need a jacket based on the weather in Hertfordshire, UK 1 second ago
Why? Because it's not very warm out.
55°F13°C & Cloudy
Wind is 4 mph6 km/h from the NW, gusting to 8 mph13 km/h
| May 21 | ||||
| 8pm | 55°F13°C | 4 mph7 km/h NW | Cloudy | |
| 9pm | 54°F12°C | 4 mph7 km/h NW | Cloudy | |
| 10pm | 54°F12°C | 5 mph8 km/h NW | Cloudy | |
| 11pm | 54°F12°C | 5 mph8 km/h NW | Drizzle | |
| May 22 | ||||
| 12am | 54°F12°C | 5 mph9 km/h W | Drizzle | |
| 1am | 54°F12°C | 6 mph10 km/h W | Rain | |
| 2am | 54°F12°C | 6 mph10 km/h W | Drizzle | |
| 3am | 54°F12°C | 8 mph12 km/h W | Drizzle | |
| 4am | 55°F13°C | 8 mph13 km/h W | Drizzle | |
| 5am | 57°F14°C | 9 mph14 km/h W | Drizzle | |
| 6am | 58°F14°C | 10 mph16 km/h W | Drizzle | |
| 7am | 59°F15°C | 11 mph17 km/h W | Cloudy | |
| Date | Low | High | Wind | Day | Night |
|---|---|---|---|---|---|
| May 21 | 54°F12°C | 61°F16°C | 10 mph17 km/h from W | Drizzle | Drizzle |
| May 22 | 50°F10°C | 60°F16°C | 13 mph21 km/h from W | Cloudy | Mostly Cloudy |
| May 23 | 47°F8°C | 63°F17°C | 8 mph13 km/h from SW | Mostly Cloudy | Mostly Clear |
| May 24 | 46°F8°C | 66°F19°C | 4 mph6 km/h from S | Partly Cloudy | Mostly Cloudy |
| May 25 | 51°F11°C | 67°F19°C | 6 mph10 km/h from S | Mostly Cloudy | Mostly Cloudy |
| May 26 | 50°F10°C | 66°F19°C | 7 mph12 km/h from NW | Mostly Cloudy | Mostly Cloudy |
| May 27 | 50°F10°C | 68°F20°C | 7 mph11 km/h from W | Partly Cloudy | Drizzle |
Yes
Low of 50°F10°C, High of 60°F16°CWind: 13 mph21 km/h
Precipitation: 21% rain