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 FRIDAY 15 MARCH 2024
Week 1 (Monday 18 March to Sunday 24 March)
Low pressure is expected to remain generally dominant to the northwest of Ireland, with higher pressure favoured to the south. This will likely produce a mainly south to southwest airflow for the period. As a result, precipitation is expected to be above average across the west and north of the country, with conditions closer to average amounts in the south and east. Temperatures will likely be above average countrywide.
Week 2 (Monday 25 March to Sunday 31 March)
A southward shift in low pressure is strongly signalled for week 2, with low pressure currently looking likely to become anchored to the south or southwest of Ireland. This would likely mean wetter than average conditions across the south and east of the country with nearer normal rainfall amounts in the west and northwest. Mean temperatures are predicted to to be around average.
Week 3 (Monday 01 April to Sunday 07 April)
A tendency towards low pressure to be maintained to southwest of Ireland is predicted as we go into week 3. Rainfall amounts would likely continue above average in most areas in this scenario, but in parts of the west and northwest rainfall would be closer to average or slightly below. Slightly above average temperatures are predicted across the bulk of the country but trending near average in western and northwestern parts.
Week 4 (Monday 08 April to Sunday 14 April)
Confidence in the forecast reduces as we head into week 4. There is a weak signal towards low pressure to the southwest but no strong signal for either low or high pressure to dominate. Temperatures are predicted to be close to average with above average precipitation favoured.
SEASONAL OUTLOOK FOR APRIL MAY JUNE (AMJ)
- The signal from the C3S seasonal models for Ireland during the AMJ period is for slightly above average temperatures. Rainfall is likely to be above or close to average overall.
- As mean temperatures during AMJ are signalled to be above average overall, all three months are likely to trend between 0.5 and 1.0°C above normal, with the strongest signals for May and June. However, there is the possibility of colder outbreaks from the north and northeast at times at the beginning of the period in April.
- The rainfall forecast is less certain, with the likelihood of wetter than average conditions in April, though there is the potential for drier spells in May and June in particular.
- The sea surface temperatures around Irish coasts and over the Atlantic are expected to continue slightly above average during AMJ, trending 0.2 to 1.0°C degrees higher than normal generally, with the highest anomalies expected in the Irish Sea.