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: 29/05/2026 12:00
Week 1 – Monday 01st June to Sunday 07th June
The signal is for mostly unsettled conditions for the first week of meteorological summer. Low pressure systems
will track close to the north of the country or over it bringing above average rainfall throughout the country in a
westerly airflow. Temperatures will likely be close to normal for most but could be a little below in parts of the
west and southwest. Rainfall amounts will need to be monitored for potential impacts.
Week 2 – Monday 08th June to Sunday 14th June
For Week 2, the signal is for improving conditions as high pressure to the south begins to build up towards the
country. There will still be above average rainfall amounts, most likely for western and northern areas, especially in
the earlier part of the week. Drier than average conditions are expected in parts of the south and south-east with
more normal amounts elsewhere. Temperatures will likely be around normal.
Week 3 – Monday 15th June to Sunday 21st June
For Week 3, high pressure looks set to dominate our weather bringing drier and warmer than average conditions. A
very slack airflow could lead to fog or sea fog at times.
Week 4 – Monday 22nd June to Sunday 28th June
Week 4 is indicated to be similar to Week 3 with high pressure dominating. Drier and warmer than average
conditions are expected to continue.
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.