The extended range forecast, which includes the monthly and seasonal forecasts, can at times provide an insight into weather patterns in the months ahead. However, they should not be used for specific planning purposes as they have generally low skill compared with the 10-day forecast. This is because forecasts beyond one week become increasingly uncertain due to the chaotic nature of the atmosphere. Further information can be found here Monthly and seasonal forecast explained.
Images: Shutterstock/gabriel12. Met Éireann HQ during Storm Emma 2018
MONTHLY FORECAST, ISSUED TUESDAY 20 MAY 2025
Week 1 (Monday 26 May to Sunday 01 June)
Low pressure to the north will dominate the weather in week 1. This will bring more unsettled conditions with above average precipitation for this time of year. Mean air temperatures will be close to the norm for this time of year.
Week 2 (Monday 02 June to Sunday 08 June)
|While confidence for week 2 is lower, there is a slight signal that low pressure will be dominant. This will bring unsettled conditions with above average rainfall amounts over most of the country. Mean air temperatures are also expected to be slightly above average for most of the country.
Week 3 (Monday 09 June to Sunday 15 June)
There is increasing uncertainty in the forecast for week 3. High pressure is expected to be the dominant factor for the weather this week. This is expected to bring with it below average rainfall amounts and above average mean air temperatures for most of the country.
Week 4 (Monday 16 June to Sunday 22 June)
In week 4 the forecast confidence is low. Little change is expected this week with the high pressure expected to continue dominating the weather over Ireland. Once again, this will be expected to bring below average rainfall and above average mean air temperatures to most of the country.
SEASONAL OUTLOOK FOR June July August (JJA)
The signal from the C3S seasonal models for Ireland during the JJA period is for above average temperatures with average rainfall overall.
Mean temperatures during JJA are very likely to be above average. Temperatures are likely to trend between 0.5 and 1.0°C above average generally for the three-month period, with a signal for mean temperatures to trend between 1.0°C and 2.0°C above average for the south and east during June.
The rainfall forecast is less certain with the potential for both wetter and drier periods through JJA. There is a signal for wetter than average conditions in June and drier than average conditions in August, while July has no definitive signal either way.
The sea surface temperatures around Irish coasts and over the Atlantic to the west and south of Ireland are expected to be above average during JJA, trending 0.5 to 2.0°C higher than normal generally. Sea surface temperatures are expected to be highest in comparison to normal off the south coast.