The south-east is known as the “sunny south-east” with reason: it has the most sunshine and among the lowest rainfall on the island. Kilkenny’s indoor sights and pubs work in any weather; Glendalough and Cashel are best on a dry day.
Season by season
Spring (March–May)
Bluebells in the woods at Glendalough, lambs in the fields and fewer coaches. Sites that close or shorten hours in winter are fully open from Easter.
Summer (June–August)
Warmest inland; the arts festival fills Kilkenny in August. Glendalough’s car parks are full by late morning at weekends, and Newgrange tickets sell out.
Autumn (September–October)
Beech and oak colour in the Wicklow valleys and along the Nore; harvest food festivals. A lovely, calm time to tour.
Winter (November–February)
Cold, clear days suit Cashel and Kilkenny; mountain roads in Wicklow may be icy. Yulefest brings Christmas markets, and the solstice draws crowds to Newgrange.
Month by month
| Month | Avg high / low | Wet days | Daylight | Our verdict |
|---|---|---|---|---|
| January | 8° / 2°C | ≈13 | ≈8 h | Quiet & cheap |
| February | 9° / 2°C | ≈10 | ≈9.5 h | Quiet & cheap |
| March | 11° / 3°C | ≈12 | ≈12 h | Good |
| April | 13° / 4°C | ≈11 | ≈14 h | Good |
| May | 16° / 7°C | ≈11 | ≈16 h | Best |
| June | 19° / 10°C | ≈10 | ≈17 h | Best |
| July | 21° / 12°C | ≈11 | ≈16.5 h | Peak season |
| August | 20° / 11°C | ≈12 | ≈14.5 h | Peak season |
| September | 18° / 9°C | ≈11 | ≈12.5 h | Best |
| October | 14° / 7°C | ≈13 | ≈10.5 h | Good |
| November | 11° / 4°C | ≈12 | ≈8.5 h | Quiet & cheap |
| December | 9° / 2°C | ≈13 | ≈7.5 h | Quiet & cheap |
Approximate long-term averages, rounded; daylight is the approximate time between sunrise and sunset mid-month. Irish weather changes quickly — pack for showers in any month.
Festivals & events
- Mid-March Kilkenny Tradfest — traditional music around St Patrick’s Day.
- June bank holiday Cat Laughs Comedy Festival, Kilkenny.
- Summer Hurling championship matches at Nowlan Park.
- August Kilkenny Arts Festival — ten days of classical music, theatre and visual art; Spraoi street-arts festival in Waterford.
- Late October Savour Kilkenny food festival; Kilkenomics, a festival of economics and comedy, in November.
- Late October – November Wexford Festival Opera.
- December Yulefest Kilkenny; Winterval in Waterford; the winter solstice at Newgrange (18–23 December).
Crowds & booking ahead
Kilkenny is busiest at weekends all year and during Cat Laughs and the arts festival. Glendalough is the pinch point: on sunny summer Sundays the valley’s car parks close when full, so arrive early or late. Book Newgrange for any date between May and September well in advance.
