Typically the average temperate in Hemel Hempstead in the month of May is 11. With the average high being 17 and lows being 9. The table below has some further insights:
| Month | Degrees Celsius |
|---|---|
| Temperature | 11 |
| High Temperature | 17 |
| Low Temperature | 9 |
Useful Links: Hemel Hempstead Weather: Average Weather & Yearly Climate