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: 22/05/2026 14:30
Week 1 – Monday 25th May to Sunday 31st May
High Pressure will dominate Ireland’s weather throughout much of the week, bringing largely dry and settled weather but there is the potential for more changeable conditions by the weekend. Mean air temperatures will trend above average, with the warmest conditions early in the week. Rainfall totals will be below normal across the country. However, there is the chance of some sharp showers developing later in the week which may bring localised higher totals.
Week 2 – Monday 01st June to Sunday 07th June
Weather conditions are likely to turn increasingly mixed and changeable for the first week of June with more Low Pressure influence. Mean air temperatures are likely to remain slightly above the climatological average, especially in the east. Rainfall totals look set to be above the June norm with showers and longer spells of rain moving through at times.
Week 3 – Monday 08th June to Sunday 14th June
For the second week of June, there are tentative signs for High Pressure to become a more notable feature of Ireland’s weather, bringing more settled weather conditions. Mean air temperatures are forecast to be above the June average nationwide. Rainfall amounts are currently predicted to be below normal.
Week 4 – Monday 15th June to Sunday 21st June
At Forecast Week 4, there remains a moderate signal for High Pressure to be positioned near Ireland bringing fairly settled weather overall. Temperatures are forecast to be above the climatological average and rainfall amounts are predicted to be below 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.