National Forecast

Issued at: 20 September 2026 19:00

TODAY - Sunday 20th September

Mostly dry but cloudy this evening with some light rain or drizzle in the west and southwest, along with mist and hill fog. Light to moderate southerly or variable breezes.

TONIGHT

Cloud will continue to build from the west as the night goes on, bringing patchy light rain and drizzle in places. There will be mist and hill fog too. Lowest temperatures of 10 to 15 degrees early in the night, becoming milder and humid overnight, with light to moderate southerly or variable breezes.

TOMORROW - Monday 21st September

Tomorrow will be mostly cloudy and dry with just patches of light rain or drizzle in places. There will be mist and hill fog in the morning, but some sunny spells will break through during the afternoon and evening. Warm and humid, with highest temperatures of 17 to 22 or 23 degrees, coolest near western and southwestern coasts, all in light to moderate southwesterly breezes.

National Outlook

Overview: Turning rather mild and humid for early next week but still some rain and drizzle at times. Plenty of dry weather interludes also.

Monday Night: A very mild and humid night with a lot of dry weather and some clear spells, but still some mist and drizzle patches in the west and northwest. Fog patches possible in the south overnight too with lowest temperatures of 13 to 16 degrees in light to moderate southerly winds.

Tuesday: Becoming overcast during the morning with outbreaks of rain but more persistent rain will push in across Connacht and Ulster. Staying cloudy throughout the day with light southerly winds and highs of 17 to 20 degrees.

Tuesday Night: Cloudy with rain mainly across the west and northwest. Drier weather elsewhere but there will be some patchy outbreaks of light rain at times. Mist patches forming overnight too with light winds and lows of 11 to 14 degrees.

Wednesday: Cloudy, wet and unsettled to start but the rain will gradually move off the country in the morning leaving behind cloud for the afternoon and some dry weather and plenty of clear spells developing. Highs of 14 to 17 degrees with light northwesterly winds.

Further outlook: Current indications suggest that the unsettled weather will return for Thursday with some wet and possibly very windy conditions in store.