Ireland Set for Brief Warm Spell Before Sudden Arctic Chill, Warn Forecasters

Ireland is set to experience its warmest spell of 2026 so far this week, with temperatures forecast to rise significantly before an abrupt return to colder conditions, according to Met Éireann and leading weather experts.

Forecasters predict that temperatures could reach between 17°C and 18°C in the coming days—levels that may temporarily make parts of Ireland warmer than regions of Spain. The unseasonably mild conditions are expected to bring clear skies and extended sunshine across much of the country.

However, meteorologists caution that the warm spell will be short-lived. Alan O'Reilly, who operates the widely followed Carlow Weather platform, has warned of an incoming surge of Arctic air that could significantly lower temperatures early next week.

“Temperatures will peak around 17°C on Thursday, marking the warmest day of the year so far, with a few fine days to follow. However, people should not put away their winter clothing just yet,” he noted, highlighting forecast models that indicate a sharp drop in temperatures.

According to the national outlook issued by Met Éireann, conditions will remain largely dry through the end of the week, with clear nights and the development of fog in light winds. Daytime temperatures are expected to range from 12°C to 16°C on Friday, accompanied by sunny spells, although coastal regions in the east and northeast may remain overcast for longer periods.

Saturday is forecast to bring similar conditions, with morning fog clearing to reveal generally dry weather and hazy sunshine. However, cloud cover is expected to increase in the northwest, where light rain or drizzle may occur intermittently.

By Sunday, the weather pattern is set to shift, with increasing cloud cover and the onset of rain, particularly across Connacht and Ulster. Winds are expected to strengthen along Atlantic coastal areas as temperatures ease to between 10°C and 13°C.

Looking ahead to early next week, forecasters anticipate a marked change, with cooler, unsettled conditions prevailing. The arrival of Arctic air is expected to bring a combination of rain, showers, and breezy to windy conditions, signalling a return to more typical seasonal weather.