National Forecast
Issued at: 21 May 2026 04:30
TODAY - Thursday 21st May
Mostly cloudy at first today with patchy outbreaks of rain and drizzle, heavy in places, becoming mainly confined to north and northwest counties by mid-afternoon. Mist and fog in parts too. However, drier and brighter conditions will gradually extend from the south with hazy sunshine developing in places. Highest temperatures of 14 to 19 degrees, in a moderate, occasionally fresh south to southeast breeze.
TONIGHT
Tonight will be cloudy and humid with patches of mist and drizzle, but overall a lot of dry weather away from southern and western fringes. Another mild night, with lowest temperatures of 11 to 13 degrees, in just light to moderate southerly breezes.
TOMORROW - Friday 22nd May
Friday will begin mild and cloudy with patches of mist and drizzle across the country. While sunny spells will gradually develop, some sharp showers will develop in places too, currently the focus of these will be across Ulster. Mild with highest temperatures of 17 to 20 degrees generally, somewhat cooler though for southern areas, where sea-fog may encroach. Southwest breezes will be no more than moderate in strength.
National Outlook
Overview: Temperatures will continue to trend upwards with warm or very warm conditions. High pressure will bring mostly dry and settled weather too. Sea fog may impinge in some areas however.
Friday night: Any lingering showers will die out early on Friday night with a dry and cloudy night following. Mist and fog may set in though, especially for southeast counties. Lowest temperatures 9 to 12 degrees, in just light southwest or variable breezes.
Saturday: Dry with warm sunny spells developing, and no more than moderate southwest breezes. Highest temperatures of 17 to 21 degrees generally, though it will be a little cooler in some coastal fringes.
Sunday: Similarly, it will be another warm day with spells of sunshine. However, cloudier skies will build in parts too. Highest temperatures of 18 to 22 degrees, in just light southerly or variable breezes.
Early Next Week: High pressure looks set to dominate into early next week, bringing a continuation of the mostly settled spell with warm or very warm feeding up across the country, on a southeast continental airflow.
Temperature circle (°C): maximum and minimum temperature forecast for each day. Wind symbol (km/h): arrow points in the direction the wind is blowing. The weather and wind icons: for the time of maximum temperature and minimum temperature.