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 FRIDAY 11 JULY 2025
Week 1 (Monday 14 July to Sunday 20 July)
It looks set to be a rather changeable and unsettled week with Low Pressure the dominant feature of Ireland’s weather. A south or southwesterly air-flow will predominate which will result in higher than average temperatures across most of the country. Rainfall amounts are forecast to be above the seasonal norm with the largest rainfall totals predicted in western and northwestern regions.
Week 2 (Monday 21 July to Sunday 27 July)
There is a fair amount of uncertainty by Forecast Week 2. High Pressure looks set to build in across Ireland at times which will bring a more mixed weather outlook with good dry periods forecast. Air temperatures are forecast to stay above normal across the country and much of northwest Europe also. Rainfall amounts will be down on the preceding week with forecast rainfall totals of around or slightly below the climatological average for late July.
Week 3 (Monday 28 July to Sunday 03 August)
There are some weak signals for the weather over Ireland and northern Europe to turn rather unsettled in Forecast Week 3 with Low Pressure the dominant driver of the weather. Mean air temperatures are forecast to be around the climatological average. Rainfall totals are projected to be slightly above the seasonal norm.
Week 4 (Monday 04 August to Sunday 10 August)
Forecast confidence decreases in Forecast Week 4 and as we enter into the first full week of August. However, there are some weak signals for the weather to be mixed and changeable with Low Pressure the more dominant influencer of Ireland’s weather. Mean air temperatures are forecast to be around the August average whilst rainfall totals are predicted to be above normal.
Seasonal Outlook for July August September (JAS)
The signal from the C3S seasonal models for Ireland during the JAS period is for above average temperatures with average to below average rainfall overall.
Mean temperatures during JAS are very likely to be above average. Temperatures are likely to trend between 0.5 and 2.0°C above average generally with the highest mean temperatures, compared to average, signalled during July and August.
The rainfall forecast is less certain, with the potential for both wetter and drier periods through JAS, however, there is a signal for slightly drier than average conditions overall.
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 JAS, 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.