Click on a day for an hourly weather forecast
The temperatures in Hennef in May are quite cold with temperatures between 7°C and 18°C, warm clothes are a must.
You can expect about 3 to 8 days of rain in Hennef during the month of May. It’s a good idea to bring along your umbrella so that you don’t get caught in poor weather.
Our weather forecast can give you a great sense of what weather to expect in Hennef in May 2026.
If you’re planning to visit Hennef in the near future, we highly recommend that you review the 14 day weather forecast for Hennef before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 4° / -1° | 9 | 13 | 9 | 61 mm | Awful | Hennef in January |
| February | 6° / 0° | 7 | 15 | 6 | 46 mm | Awful | Hennef in February |
| March | 11° / 2° | 6 | 23 | 2 | 51 mm | Bad | Hennef in March |
| April | 15° / 5° | 4 | 24 | 1 | 43 mm | Good | Hennef in April |
| May | 18° / 7° | 6 | 25 | 0 | 79 mm | Good | Hennef in May |
| June | 22° / 11° | 6 | 25 | 0 | 75 mm | Good | Hennef in June |
| July | 24° / 13° | 5 | 26 | 0 | 79 mm | Perfect | Hennef in July |
| August | 24° / 13° | 4 | 27 | 0 | 71 mm | Perfect | Hennef in August |
| September | 21° / 10° | 4 | 26 | 0 | 46 mm | Good | Hennef in September |
| October | 15° / 6° | 5 | 26 | 0 | 53 mm | Good | Hennef in October |
| November | 10° / 4° | 7 | 22 | 1 | 53 mm | Bad | Hennef in November |
| December | 6° / 1° | 8 | 17 | 6 | 67 mm | Awful | Hennef in December |