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.
MONTHLY FORECAST, ISSUED TUESDAY 20 FEBRUARY 2024
Week 1 (Monday 26 February to Sunday 03 March)
Week 1 will be largely unsettled with low pressure systems often tracking close to Ireland. A predominantly westerly airflow will steer frontal systems across the country at times, with rainfall amounts expected to be above average for most of the country. Rainfall will be closer to normal in southern coastal areas. Mean temperatures will be around normal, possibly slightly warmer than average in some western coastal areas.
Week 2 (Monday 04 March to Sunday 10 March)
There is a trend towards more settled conditions in Week 2 as low pressure weakens and high pressure begins to have more of an influence on our weather. While occasional showers and spells of rain are likely, rainfall amounts will be lower than normal for most of the country. Coastal regions of the west will be the exception, with near average rainfall there. Indications suggest that it will become warmer, with mean temperatures increasing above average nationwide.
Week 3 (Monday 11 March to Sunday 17 March)
While there is increased uncertainty in the trend for Week 3, current indications suggest that low pressure to the south of Ireland will establish an easterly airflow over the country. This will bring showers at times, which will result in slightly higher than average rainfall in some areas, particularly on eastern facing coasts. However, rainfall for most of the country will be near normal. It will be slightly warmer than average across the country also.
Week 4 (Monday 18 March to Sunday 24 March)
Current indications suggest that Week 4 will be generally settled with an easterly airflow likely to bring some showers, especially to eastern areas. Many parts of the country will be drier than average, though rainfall over the eastern half of the country will be close to normal. Temperatures will decrease slightly to around average nationwide.
SEASONAL OUTLOOK FOR MARCH APRIL MAY (MAM)
The signal from the C3S seasonal models for Ireland during the MAM period is for slightly above average temperatures. Rainfall is likely to be above or close to average. Mean temperatures during MAM are signalled to be above average overall.
March has the possibility of colder outbreaks from the north and northeast at times. April and May however are expected to be above average and trend between 0.5 and 1.0 °C above average.
The rainfall forecast is less certain, with the likelihood of slightly wetter than average conditions overall, though there is the potential for drier spells in March and May in particular.
The sea surface temperatures around Irish coasts and over the Atlantic are expected to continue slightly above average during MAM, trending 0.2 to 0.5 °C higher than normal in the Atlantic near Ireland, and up to 1.0°C higher than normal in the Irish Sea.