Portlaoise climate — normals and trends
Portlaoise (Ireland) has a temperate oceanic climate (Cfb) under the Köppen-Geiger classification. Its mean annual temperature is 9.7 °C and it receives 792 mm of precipitation per year.
These figures are normals computed over 86 complete calendar years, from 1940 to 2025, using ERA5 reanalysis data from the Copernicus programme.
The warmest month is July (15.3 °C on average) and the coldest is January (4.8 °C). Rainfall peaks in December.
Portlaoise averages 29 frost days, 0 hot days (≥ 30 °C) and 149 rainy days per year.
Portlaoise has warmed by +0.6 °C between 1940 and 2025, or +0.07 °C per decade. This trend is statistically significant.
The number of frost days there went from about 36 to 22 per year over the period.
The hottest day of the period reached 30.2 °C (on 29 June 1976) and the coldest -14.0 °C (on 12 January 1982).
Data from ERA5 reanalysis (Copernicus Climate Change Service), redistributed under a CC-BY 4.0 licence. Normals are recomputed whenever the archive is updated.
Climate normals · ERA5
PortlaoiseLeinster
- coords
- 53.03°, -7.30°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
9.7°C
Average daily high
12.7°C
Average daily low
6.7°C
Annual rainfall
792mm
Sunshine / day
6.7h
Mean relative humidity
82%
Average peak wind
19.8km/h
Seasonal range
10.5°C
Frost days (< 0 °C)
29 d/yr
Hot days (≥ 30 °C)
0 d/yr
Rainy days (≥ 1 mm)
149 d/yr
Annual snowfall
11.0 cm
Average feels-like high
10.1 °C
Average feels-like low
3.8 °C
Average peak gust
42.4 km/h
Tropical nights (≥ 20 °C)
0 d/yr
Solar radiation
9.5 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+0.6 °C
since 1940
+0.1 °C per decade · r² = 0.12 · p = 0.001
Trend fitted by linear regression (ordinary least squares) on annual means. A trend is shown only when it is statistically significant (p < 0.05).
A climograph overlays rainfall (bars) and temperature (line): the standard reading in climatology, where you can see at a glance whether the warm season is also the dry one.
Records for the period
Hottest day
30.2 °C
29 June 1976
Coldest day
-14.0 °C
12 January 1982
Wettest day
66 mm
25 August 1986
Windiest day
63.0 km/h
24 December 1997
Strongest gust
135.0 km/h
23 April 1947
Hottest feels-like
32.7 °C
13 July 1983
Coldest feels-like
-19.3 °C
12 January 1982
Snowiest day
21.5 cm
8 December 1954
Sunniest day
16.7 h
19 June 1940
Normals computed over complete calendar years 1940–2025.
A specific year
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Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | 7.1 °C | -0.1 °C | 83 mm | +12 mm |
| Feb | 8.7 °C | +1.0 °C | 69 mm | +12 mm |
| Mar | 11.5 °C | +1.9 °C | 25 mm | -35 mm |
| Apr | 14.7 °C | +2.9 °C | 79 mm | +22 mm |
| May | 17.4 °C | +2.7 °C | 59 mm | -8 mm |
| Jun | 18.4 °C | +1.1 °C | 55 mm | -7 mm |
| Jul | 20.1 °C | +1.4 °C | 64 mm | +1 mm |
| Aug | 19.8 °C | +1.4 °C | 37 mm | -34 mm |
| Sep | 16.0 °C | -0.3 °C | 102 mm | +36 mm |
| Oct | 13.3 °C | +0.2 °C | 97 mm | +22 mm |
| Nov | 10.6 °C | +1.0 °C | 126 mm | +58 mm |
| Dec | 9.0 °C | +1.2 °C | 93 mm | +16 mm |
The year's extremes
What was the weather like that day?
Your birthday, a wedding, a memorable trip: discover the actual weather for any date since 1940.
Frequently asked questions
What is the climate of Portlaoise?
Portlaoise has a temperate oceanic climate (Köppen Cfb). Over 1940-2025, the average annual temperature is 9.7 °C and it receives 792 mm of precipitation per year.
What is the hottest day ever recorded in Portlaoise?
The hottest day measured in Portlaoise between 1940 and 2025 was 29 June 1976, reaching 30.2 °C.
What is the coldest day in Portlaoise?
The coldest day measured in Portlaoise between 1940 and 2025 was 12 January 1982, at -14.0 °C.
Does it snow in Portlaoise?
Yes. Portlaoise gets on average 11.0 cm of snow per year and has around 29 frost days.
Has the climate of Portlaoise warmed?
Yes: Portlaoise warmed by +0.6 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Portlaoise?
The wettest day measured in Portlaoise between 1940 and 2025 was 25 August 1986, with 66 mm of rain in 24 hours.
What was the windiest day in Portlaoise?
The windiest day measured in Portlaoise between 1940 and 2025 was 24 December 1997, with winds reaching 63.0 km/h.
What is the warmest month in Portlaoise?
The warmest month in Portlaoise is July (15.3 °C on average); the coldest is January (4.8 °C).
How much does it rain in Portlaoise?
Portlaoise receives on average 792 mm of precipitation per year, spread over about 149 rainy days.
Is it sunny in Portlaoise?
Portlaoise gets on average 6.7 hours of sunshine per day, roughly 2,446 hours per year over 1940-2025.
What is the biggest single-day snowfall in Portlaoise?
The heaviest 24-hour snowfall measured in Portlaoise between 1940 and 2025 was 8 December 1954, with 21.5 cm.
Are there tropical nights in Portlaoise?
Almost never: tropical nights (temperature staying above 20 °C) are virtually non-existent in Portlaoise.
What was the most extreme apparent temperature in Portlaoise?
In Portlaoise, between 1940 and 2025, the highest apparent temperature reached 32.7 °C on 13 July 1983, and the lowest was -19.3 °C on 12 January 1982.
Compare Portlaoise with another city
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Nearby cities
The climate around Portlaoise