Castleisland is among the wettest of Irish towns: 1,339 mm of rain a year
Expect July afternoons of about 19.7°C. Of the 5 towns of 2,500+ in County Kerry, it has the coldest January nights. Since 1981–2010, the year has warmed by 0.3°C, most of all in April. Homes need heating from November to April, the months averaging under 10°C.
Met Éireann 1991–2020 averages for the town’s own square kilometre.
A year in Castleisland at a glance
Each month’s typical high and low, in °C.
What stands out about Castleisland’s climate
Compared with Irish towns, with its place among towns of 2,500+ in County Kerry beside it.
What a year in Castleisland feels like
Typical highs and lows by season and by month, from Met Éireann’s 1991–2020 averages.
About 1,339 mm of rain a year
November is the wettest month and May the driest. 3rd wettest of 5 towns of 2,500+ in County Kerry. The wettest month brings about 2.0 times the rain of the driest.
Rain by month
Millimetres
Living with Castleisland’s climate
What the averages mean for a garden, a free afternoon and a bad-weather day.
Highs of 17–27°C with lows of 8°C or more: Jun, Jul, Aug and Sep.
Parks & trails →Averages smooth over storms, floods and heatwaves; Castleisland’s hazards page covers the risks.
Flood & hazards →Met Éireann’s nearest station: Valentia
Valentia is 63 km south-west of Castleisland, the nearest of the 25 synoptic stations where Met Éireann records the weather around the clock. The station stands 24 m above sea level; Castleisland’s centre, 33 m.
| Month | High | Low | Rain | Air frosts | Sun (hours) |
|---|---|---|---|---|---|
| January | 9.9°C | 5.0°C | 184 mm | 2.0 | 52 |
| February | 10.0°C | 4.9°C | 137 mm | 1.9 | 70 |
| March | 11.0°C | 5.3°C | 114 mm | 1.4 | 118 |
| April | 12.6°C | 6.4°C | 104 mm | 0.2 | 165 |
| May | 14.8°C | 8.6°C | 92 mm | 0.0 | 179 |
| June | 16.7°C | 10.8°C | 100 mm | 0.0 | 168 |
| July | 17.9°C | 12.7°C | 113 mm | 0.0 | 137 |
| August | 18.0°C | 12.5°C | 114 mm | 0.0 | 134 |
| September | 17.0°C | 11.2°C | 126 mm | 0.0 | 117 |
| October | 14.5°C | 9.1°C | 171 mm | 0.0 | 91 |
| November | 11.9°C | 6.9°C | 187 mm | 0.5 | 56 |
| December | 10.5°C | 5.7°C | 176 mm | 1.8 | 40 |
| Year | 13.7°C | 8.3°C | 1,617 mm | 8 | 1,327 |
The table is Valentia’s own record, averaged over 1991–2020 from its daily readings (ours, not a Met Éireann table). The rest of the page is Met Éireann’s 1 km grid at Castleisland itself: past 40 km, the station’s frosts and sunshine don’t stand for the town.
How Castleisland compares
Against the 321 Irish towns and city neighbourhoods of 2,500 or more, each read from Met Éireann’s grid at its own centre, and its place among towns of 2,500+ in County Kerry.
Warmer than it used to be
Castleisland’s 1991–2020 average is 0.3°C warmer than 1981–2010’s. The biggest change is in April (+0.4°C).
A year’s rain is 1,339 mm, up 3% from 1,305 mm.
Change by month
The two periods share 1991–2010, so the gap is a decade’s step, not the change between two separate 30-year periods.
Nearby towns’ climate
The nearest towns of 1,000+ within 19 km: a hill, a valley or the sea can make a real difference over a short distance.
| Town | July high | January low | Rain a year |
|---|---|---|---|
| Castleisland | 19.7°C | 3.4°C | 1,339 mm |
| Tralee 17 km | 19.5°C about the same | 3.9°C 0.5°C milder | 1,312 mm |
Castleisland weather by month
Average daily high and low, mean temperature and rain, 1991–2020, for the town itself (Met Éireann’s 1 km grid).
| Month | High | Low | Mean | Rain |
|---|---|---|---|---|
| January | 9.5°C | 3.4°C | 6.5°C | 145 mm |
| February | 9.9°C | 3.3°C | 6.6°C | 111 mm |
| March | 11.5°C | 4.1°C | 7.8°C | 96 mm |
| April | 13.8°C | 5.3°C | 9.5°C | 85 mm |
| May | 16.4°C | 7.7°C | 12.0°C | 77 mm |
| June | 18.6°C | 10.2°C | 14.4°C | 82 mm |
| July | 19.7°C | 12.2°C | 15.9°C | 93 mm |
| August | 19.6°C | 11.9°C | 15.7°C | 105 mm |
| September | 18.0°C | 10.2°C | 14.1°C | 107 mm |
| October | 14.7°C | 7.8°C | 11.2°C | 132 mm |
| November | 11.6°C | 5.4°C | 8.5°C | 154 mm |
| December | 9.8°C | 3.9°C | 6.9°C | 153 mm |
| Year | 14.4°C | 7.1°C | 10.8°C | 1,339 mm |
Where Castleisland’s numbers come from
Averages over 30 years, not a forecast.
- Temperature and rain: Met Éireann’s 1991–2020 averages on its 1 km grid (Climatological Notes 22 and 23), read at the grid point nearest Castleisland’s population centre (0.2 km away).
- Weather station: the nearest of Met Éireann’s 25 synoptic stations, Valentia, 63 km south-west, from Met Éireann’s station list.
- Frosts and degree days: Valentia’s daily readings, 1991–2020, in the station table only: past 40 km they don’t stand for the town.
- Then and now: Met Éireann’s 1981–2010 averages on the same 1 km grid, at the same point.
- Altitudes: the town’s ground from the Copernicus GLO-30 surface model (a few metres high in built-up places), the station’s from Met Éireann.
- Comparisons: every Irish town and city neighbourhood of 2,500 or more, read the same way; the five city totals are left out.
- Not on this page: sunshine, frost days, warm days, snow and wind. Met Éireann publishes no 1991–2020 grid for them, only tables for its stations, so no town has a figure of its own.
Met Éireann 30-year averages · Met Éireann open data. Under Creative Commons Attribution 4.0 (CC BY 4.0).
Questions about Castleisland’s climate
How warm does Castleisland get in summer?
The warmest month is July, when afternoons average 19.7°C.
How cold does Castleisland get in winter?
February nights average 3.3°C, the coldest of the year. Met Éireann counts frosts only at its weather stations, so there is no frost count for the town itself.
How much rain does Castleisland get?
About 1,339 mm a year, more than 96% of Irish towns. November is the wettest month (154 mm) and May the driest (77 mm).
How sunny is it?
Met Éireann publishes its 1991–2020 sunshine averages for its weather stations only, not on the 1 km grid this page reads, so there is no sunshine figure for Castleisland itself. Its nearest synoptic station is Valentia.
Are these figures for Castleisland itself?
Yes: they are Met Éireann’s 1991–2020 averages on its 1 km grid, read at Castleisland’s population centre. The nearest of its synoptic weather stations, Valentia, is 63 km south-west.
Where do these figures come from?
Met Éireann’s 1991–2020 climate averages, published as maps of Ireland in 1 km squares (Climatological Notes 22 and 23); the page reads the square at Castleisland’s population centre. They are 30-year averages, not a forecast.
Copyright Met Éireann. Source: www.met.ie. This data is published under a Creative Commons Attribution 4.0 International (CC BY 4.0) licence. Met Éireann does not accept any liability whatsoever for any error or omission in the data, their availability, or for any loss or damage arising from their use. This material has been modified from the original: TownRatings reads the 1 km grid at each town’s population centre. Today’s forecast for Castleisland →
Contains Central Statistics Office (CSO) data, Census 2022, and Tailte Éireann boundaries (CSO Urban Areas, Small Areas, local electoral areas, constituencies), under Creative Commons Attribution 4.0 (CC BY 4.0).