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
Forecast issued Friday, 13th of March 2026
Week 1 – Monday 16th March to Sunday 22nd March
For week 1, low pressure is likely to dominate the weather at first with rain, showers and windy conditions. There is a signal then for conditions to become more settled from around midweek. Overall, mean air temperatures are likely to be warmer than average by 1 or 2 degrees. Rainfall amounts are signalled to be lower than average in
most places, except for the northwest, will likely see close to average amounts of rainfall for this time of year.
Week 2 – Monday 23rd March to Sunday 29th March
While confidence in week 2 is lower, there is a signal for our weather pattern to become blocked with high pressure, centred to the north of Ireland, dominating. Current indications show drier than average conditions with slightly warmer than average mean air temperatures.
Week 3 – Monday 30th March to Sunday 05th April
There is increasing uncertainty in the forecast for week 3, with a persisting signal for high pressure to dominate, keeping conditions generally settled for the beginning of April. This would result in less than average rainfall amounts and slightly warmer than average mean air temperatures.
Week 4 – Monday 06th April to Sunday 12th April
In week 4, the forecast confidence is low. There is a slight signal for high pressure to persist north of Ireland, though a weakening in the high pressure may allow some unsettled interludes at times. Current indications show drier than average conditions in the west of the country, with rainfall amounts signalled to be around normal
elsewhere. There is a continuing signal for mean air temperatures to be slightly warmer than average.
Seasonal Outlook for April, May, and June (AMJ) forecast
The signal from the C3S seasonal models for Ireland during the AMJ period is for above average temperatures. Rainfall amounts are less certain with the possibility of precipitation trending near average overall.
Mean temperatures during AMJ are signalled to be above average overall. Temperatures are likely to trend between 0.2 and 1.0°C above average generally. The potential for warmer than average temperatures increases through the period.
The rainfall forecast is less certain with no clear signal for above or below average rainfall overall. There is potential for both wetter and drier spells within the three months.
The sea surface temperatures around Irish coasts and over the Atlantic are expected to be above average during AMJ, trending 0.2 to 1.0°C degrees higher than normal generally. Sea surface temperatures are expected to be highest in comparison to average away from northwest coasts.