Roscommon climate — normals and trends
Roscommon (Ireland) has a temperate oceanic climate (Cfb) under the Köppen-Geiger classification. Its mean annual temperature is 9.6 °C and it receives 970 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 (15.0 °C on average) and the coldest is January (4.8 °C). Rainfall peaks in December.
Roscommon averages 23 frost days, 0 hot days (≥ 30 °C) and 170 rainy days per year.
Roscommon has warmed by +0.5 °C between 1940 and 2025, or +0.06 °C per decade. This trend is statistically significant.
The number of frost days there went from about 31 to 15 per year over the period.
The hottest day of the period reached 29.6 °C (on 12 July 2025) and the coldest -11.6 °C (on 25 December 2010).
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
RoscommonConnacht
- coords
- 53.63°, -8.18°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
9.6°C
Average daily high
12.5°C
Average daily low
6.9°C
Annual rainfall
970mm
Sunshine / day
6.8h
Mean relative humidity
83%
Average peak wind
20.2km/h
Seasonal range
10.2°C
Frost days (< 0 °C)
23 d/yr
Hot days (≥ 30 °C)
0 d/yr
Rainy days (≥ 1 mm)
170 d/yr
Annual snowfall
12.3 cm
Average feels-like high
9.8 °C
Average feels-like low
3.9 °C
Average peak gust
42.0 km/h
Tropical nights (≥ 20 °C)
0 d/yr
Solar radiation
9.1 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+0.5 °C
since 1940
+0.1 °C per decade · r² = 0.09 · p = 0.005
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
29.6 °C
12 July 2025
Coldest day
-11.6 °C
25 December 2010
Wettest day
45 mm
9 November 1941
Windiest day
65.2 km/h
16 September 1961
Strongest gust
132.8 km/h
9 February 1988
Hottest feels-like
33.0 °C
13 July 1983
Coldest feels-like
-15.6 °C
25 December 2010
Snowiest day
13.7 cm
24 December 1968
Sunniest day
16.8 h
19 June 2025
Normals computed over complete calendar years 1940–2025.
A specific year
Pick a year and see how it compares to normal — warmer, drier or more extreme than usual?
Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | 7.0 °C | 0.0 °C | 56 mm | -31 mm |
| Feb | 8.5 °C | +0.9 °C | 109 mm | +37 mm |
| Mar | 11.6 °C | +2.1 °C | 32 mm | -41 mm |
| Apr | 14.8 °C | +3.0 °C | 94 mm | +26 mm |
| May | 17.4 °C | +2.8 °C | 46 mm | -35 mm |
| Jun | 17.8 °C | +0.8 °C | 91 mm | +17 mm |
| Jul | 19.6 °C | +1.4 °C | 70 mm | -8 mm |
| Aug | 19.3 °C | +1.4 °C | 66 mm | -23 mm |
| Sep | 15.5 °C | -0.5 °C | 112 mm | +30 mm |
| Oct | 12.9 °C | 0.0 °C | 123 mm | +32 mm |
| Nov | 10.1 °C | +0.7 °C | 120 mm | +37 mm |
| Dec | 8.7 °C | +1.0 °C | 101 mm | +8 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 Roscommon?
Roscommon has a temperate oceanic climate (Köppen Cfb). Over 1940-2025, the average annual temperature is 9.6 °C and it receives 970 mm of precipitation per year.
What is the hottest day ever recorded in Roscommon?
The hottest day measured in Roscommon between 1940 and 2025 was 12 July 2025, reaching 29.6 °C.
What is the coldest day in Roscommon?
The coldest day measured in Roscommon between 1940 and 2025 was 25 December 2010, at -11.6 °C.
Does it snow in Roscommon?
Yes. Roscommon gets on average 12.3 cm of snow per year and has around 23 frost days.
Has the climate of Roscommon warmed?
Yes: Roscommon warmed by +0.5 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Roscommon?
The wettest day measured in Roscommon between 1940 and 2025 was 9 November 1941, with 45 mm of rain in 24 hours.
What was the windiest day in Roscommon?
The windiest day measured in Roscommon between 1940 and 2025 was 16 September 1961, with winds reaching 65.2 km/h.
What is the warmest month in Roscommon?
The warmest month in Roscommon is July (15.0 °C on average); the coldest is January (4.8 °C).
How much does it rain in Roscommon?
Roscommon receives on average 970 mm of precipitation per year, spread over about 170 rainy days.
Is it sunny in Roscommon?
Roscommon gets on average 6.8 hours of sunshine per day, roughly 2,482 hours per year over 1940-2025.
What is the biggest single-day snowfall in Roscommon?
The heaviest 24-hour snowfall measured in Roscommon between 1940 and 2025 was 24 December 1968, with 13.7 cm.
Are there tropical nights in Roscommon?
Almost never: tropical nights (temperature staying above 20 °C) are virtually non-existent in Roscommon.
What was the most extreme apparent temperature in Roscommon?
In Roscommon, between 1940 and 2025, the highest apparent temperature reached 33.0 °C on 13 July 1983, and the lowest was -15.6 °C on 25 December 2010.
Compare Roscommon with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Roscommon