Click on a day for an hourly weather forecast
The temperatures in New Castle in May are quite cold with temperatures between 9°C and 22°C, warm clothes are a must.
You can expect rain for roughly half of the month of May in New Castle. We’re expecting roughly 8 to 15 days of rain, so your rubber boots and umbrella are going to see plenty of use this month if you’re keen on staying dry.
Our weather forecast can give you a great sense of what weather to expect in New Castle in May 2025.
If you’re planning to visit New Castle in the near future, we highly recommend that you review the 14 day weather forecast for New Castle before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 0° / -8° | 7 | 4 | 21 | 126 mm | Awful | New Castle in January |
| February | 2° / -7° | 7 | 4 | 18 | 126 mm | Awful | New Castle in February |
| March | 8° / -2° | 9 | 12 | 10 | 136 mm | Awful | New Castle in March |
| April | 14° / 4° | 11 | 15 | 5 | 178 mm | Bad | New Castle in April |
| May | 22° / 9° | 10 | 21 | 0 | 172 mm | Ok | New Castle in May |
| June | 26° / 13° | 9 | 21 | 0 | 185 mm | Good | New Castle in June |
| July | 28° / 16° | 10 | 21 | 0 | 183 mm | Good | New Castle in July |
| August | 28° / 15° | 8 | 23 | 0 | 134 mm | Good | New Castle in August |
| September | 24° / 12° | 6 | 24 | 0 | 130 mm | Perfect | New Castle in September |
| October | 17° / 6° | 8 | 23 | 0 | 130 mm | Ok | New Castle in October |
| November | 9° / 0° | 7 | 16 | 7 | 105 mm | Awful | New Castle in November |
| December | 4° / -3° | 9 | 8 | 15 | 130 mm | Awful | New Castle in December |