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: 19/06/2026 14:00
Week 1 – Monday 22nd June to Sunday 28th June
In week 1, high pressure is likely to dominate bringing settled conditions overall. Mean air temperatures are
forecast to be above average across the country for this time of year, and while there will be some patchy rain and
heavy showers at times, rainfall amounts are forecast to be below average nationwide.
Week 2 – Monday 29th June to Sunday 05th July
While confidence in week 2 is lower, there is a signal for settled conditions to continue with high pressure sticking
close by. Rainfall amounts are forecast to continue below average for much of the country, away from the north.
Mean air temperatures are forecast to be above normal for this time of year in the eastern half of the country and
close to normal in the west.
Week 3 – Monday 06th July to Sunday 12th July
There is increasing uncertainty in the forecast for week 3, with no distinct signal for either low or high pressure to
dominate weather conditions. There is a slight indication for mean air temperatures in eastern coastal counties to
remain above normal, while mean air temperatures elsewhere are likely to be close to normal. Rainfall amounts
are also indicated to be close to normal for this time of year.
Week 4 – Monday 13th July to Sunday 19th July
In week 4, the confidence in the forecast is low. Current indications suggest that low pressure may dominate
bringing more unsettled conditions and slightly above average rainfall amounts nationwide. Mean air
temperatures are signalled to remain close to normal.
Seasonal Outlook for July August September 2026 (JAS):
The signal from the C3S seasonal models for Ireland during the JAS period is for above-average temperatures. Rainfall is likely to be below average during the period.
Mean temperatures during JAS are signalled to be above average overall; all three months are likely to trend between 0.5 and 1.0°C above normal. The likelihood of higher-than-normal temperatures is strongest in September.
The rainfall forecast is less certain, with a weak signal for below-average rainfall overall, especially during July.
The sea surface temperatures around Irish coasts are expected to continue slightly above average during JAS, trending 0.2 to 1.0°C degrees higher than normal generally, with the highest anomalies expected off southern and eastern coasts.