SeasonMapKillarney weather in December
Ireland
December in Killarney: cold, rainy, with clean air — a good time to visit.
#12 of 12 months in Killarney · #940 of 1383 destinations to visit in December · comfort 61/100 (tier C)
Updated September 2026 · climate normals from ERA5 reanalysis
Traveller notes on Killarney in December
Other months in Killarney
Killarney's forum is candid that July weather is genuinely a grab bag — cold, rainy, calm, warm and windy have all been reported in the same month, with wetter conditions than spring and true heatwaves rare. Regulars' consistent advice is layers plus a proper rain jacket, noting July is also the single busiest month locally so accommodation books up fast regardless of forecast.
Add your own note from Killarney's card on the map.
Killarney climate normals — December
| Daytime high | 9°C / 49°F | 🧥 cold |
|---|---|---|
| Nighttime low | 5°C / 41°F | |
| Feels like (high) | 7°C / 45°F | |
| Sea temperature | 8°C / 46°F | 🥶 cold sea |
| Rainfall | 122 mm / 4.8 in | 🌧 rainy |
| Rainy days | 17 days | |
| Humidity | 90% | 💦 very humid |
| Dew point | 6°C / 42°F | |
| Sunshine | 3.4 h/day | |
| Daylight | 7.8 h | |
| Wind | 21 km/h / 13 mph | |
| Snowfall | 0.9 cm / 0.4 in | |
| Air quality (US AQI) | 33 | 🍃 good |
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
Crowds in Killarney in December
How busy the place itself is — school and mass holidays, the months an editor tagged, and how sought-after the weather makes them. Never part of the comfort score.
Peak crowdsChristmas in Killarney, Christmas break in Ireland, school holidays in 7 of the markets that fill it(estimated)
Peak crowdsBusyShoulder seasonQuiet
Best months for Killarney's weather
Ranked by this destination's own climate comfort score across the year — a different thing from how busy it gets (see Crowds above).
Toughest weatherKillarney's weather peaks May–July.
Best weatherFair weatherToughest weather
What's on in Killarney in December
Recurring seasonal events, natural spectacles, closures and holidays — curated and sourced.
- Festival
Christmas in Killarney
20 Nov – 31 Dec · usuallyChristmas & New YearCrowdedThe town runs a six-week festival with a lit trail, a market and a parade, and it draws Kerry and Cork rather than tourists. Weekends in December are as busy as August. Source ↗
Nearby, and something's on
Within 300 km of Killarney — a day trip or a short hop — with something on this month. Never part of the comfort score.
Where is Killarney?
Killarney in December — FAQ
- Is December a good time to visit Killarney?
- December in Killarney: cold, rainy, with clean air — a good time to visit. It ranks #12 of 12 months for Killarney on SeasonMap's comfort score (61/100).
- What is the weather like in Killarney in December?
- In December, Killarney averages a daily high of 9.4°C and a low of 5°C, with about 121.7 mm of rain over roughly 17.2 rainy days.
- What is the air quality in Killarney in December?
- Killarney has a mean US Air Quality Index of about 33 in December.
Other months in Killarney
Compare Killarney in December
Warmer or cooler than Killarney in December
Similar destinations in Northern Europe — December
Within 300 km: Dingle's Other Voices around 28 Nov – 10 Dec, and Dublin's Book of Kells timed tickets on 1 Jan – 31 Dec.