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 08 AUGUST 2025
Week 1 (Monday 11 August to Sunday 17 August)
Week 1 is indicating high pressure dominating our weather. This will bring predominantly settled conditions with much drier than average conditions signalled across the country. Mean air temperatures in week 1 will be mild with temperatures above normal for the time of year.
Week 2 (Monday 18 August to Sunday 24 August)
While confidence in week 2 is lower, there is a slight signal for high pressure to continue to dominate. Temperatures are indicated to continue warmer than average across the country, with a slight signal for below average rainfall too.
Week 3 (Monday 25 August to Sunday 31 August)
There is increasing uncertainty in the forecast for week 3. There is a slight signal for high pressure to persist to the north of Ireland, with indications for mean air temperatures to stay above average for this time of year. There is a continuing signal for rainfall amounts to stay below average for this week.
Week 4 (Monday 01 September to Sunday 07 September)
In week 4, the forecast confidence is low with a very slight signal for high pressure to the northwest of Ireland. Rainfall amounts are indicated to be below, or close to, average for the time of year, while mean air temperatures continue to signal warmer than average temperatures.
Seasonal Outlook for August September October (ASO)
The signal from the C3S seasonal models for Ireland during the ASO period is for above average temperatures, with average rainfall overall.
Mean temperatures during ASO are signalled to be above average. Temperatures are likely to trend between 0.5 and 1.0°C above average over the three-month period, with higher anomalies over mainland Europe during August continuing to have an influence at times.
The rainfall forecast is less certain, with the potential for both wetter and drier periods through ASO.
The sea surface temperatures around Irish coasts are expected to continue above average during ASO, trending 0.5 to 2.0°C higher than normal.