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
Issued: 19/05/2026 11:30
Week 1 – Monday 25th May to Sunday 31st May
High pressure will dominate our weather during week 1, bringing settled conditions with largely dry weather and
sunshine. It will be warmer than average nationwide with rainfall amounts below average for all areas also.
Week 2 – Monday 01st June to Sunday 07th June
Current indications suggest that high pressure will remain the dominant driver of our weather during week 2.
Settled conditions will continue as a result with warmer and drier than average conditions nationwide.
Week 3 – Monday 08th June to Sunday 14th June
Uncertainty increases in week 3 but current indications suggest that high pressure will remain nearby with
generally settled conditions. It will stay warmer than average nationwide. While some showers or spells of rain
cannot be ruled out, rainfall amounts will remain below average across the country.
Week 4 – Monday 15th June to Sunday 21st June
Confidence is low in week 4 but there is a signal for continued high pressure and settled weather across Ireland.
There may be some spells of rain or showers but rainfall amounts will be close to or slightly below average.
Temperatures will stay above normal.
Seasonal Outlook for June July August 2026 (JJA):
The signal from the C3S seasonal models for Ireland during the JJA period is for above average temperatures. Rainfall is likely to be below average during the period.
Mean temperatures during JJA are signalled to be above average overall. Temperatures are likely to trend between 0.2 and 1.0°C above average generally. The likelihood of higher than normal temperatures is strongest in August.
The rainfall forecast is less certain, with a weak signal for below average rainfall overall, especially during June and August.
The sea surface temperatures around Irish coasts are expected to continue slightly above average during JJA, trending 0.2 to 0.5°C degrees higher than normal generally.