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 TUESDAY 08 JULY 2025
Week 1 (Monday 14 July to Sunday 20 July)
The most favoured pattern for this period is for Atlantic low pressure to dominate with high pressure sequestered to the northeast over Scandinavia suggesting some level of Atlantic mobility, bringing, at times, unsettled weather with spells of rain and breezy conditions spreading from the Atlantic. Precipitation amounts are predicted to be above normal across the country. This scenario is at odds with the current deterministic IFS/ECMWF model output, which after a frontal passage clears on Monday (14th), builds the Azores high in again over Ireland indicating a broadly settled week. So there is, perhaps, a little more uncertainty in the forecast than is usual at this time frame. Temperatures do look set to remain above average throughout the period.
Week 2 (Monday 21 July to Sunday 27 July)
Current indications for week 2 suggest high pressure centred to the north will be the dominant influence with low pressure centred to the southwest in the Atlantic. Above average temperatures are signalled with near normal or slightly drier than normal conditions indicated. Some shower activity seems likely during the period.
Week 3 (Monday 28 July to Sunday 03 August)
Low pressure to the southwest with above average precipitation suggests mainly unsettled conditions during this period. The upper air situation is neutral, however, which injects a level of uncertainty into the forecast. A continued signal for above average temperatures persists.
Week 4 (Monday 04 August to Sunday 10 August)
Low pressure over eastern parts of Ireland and the UK is indicated suggesting a continuation of broadly unsettled conditions with spells of rain or showers. Again the upper air forecast is neutral which maintains an elevated level of uncertainty in the forecast. Temperature and precipitation are both signalled to be above normal through this period.
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.