National Forecast
Issued at: 21 September 2026 05:00
TODAY - Monday 21st September
Today will be warm, humid, mostly cloudy and mainly dry. There'll be a little drizzle and mist this morning. Some bright or sunny intervals will develop, the best of these further south. Highest temperatures of 17 to 22 or 23 degrees, coolest in the west and warmest in the east with light to moderate southwesterly breezes.
TONIGHT
Tonight will be mild, humid and mainly dry with some clear spells and patches of mist or fog. Cloud will increase in the northwest. Rain and drizzle will develop along the northwest coast overnight. Lowest temperatures of 12 to 15 degrees with light southerly breezes.
TOMORROW - Tuesday 22nd September
Tuesday will be mainly dry over Leinster and Munster with bright or sunny spells and perhaps one or two showers. Rain and drizzle in the northwest during the morning will spread slowly across Ulster and Connacht through the afternoon and evening. Highest temperatures of 16 to 20 for most. but between 14 and 16 degrees in the northwest. Light southerly winds.
National Outlook
Overview: Turning a bit cooler with a fair amount of dry weather and some rain or showers at times.
On Tuesday night, rain in Ulster, Connacht and west Munster will gradually move southeastwards to almost all areas overnight. Lowest temperatures of 11 to 14 degrees with light to moderate south to southwest breezes.
Through Wednesday morning, rain will gradually clear to the southeast. Drier, brighter weather will follow from the west with sunny spells developing. Cooler with highest temperatures of 14 to 17 degrees and light to moderate northwesterly winds.
Wednesday night will be dry with clear spells. Cloud will increase in the west overnight. Lowest temperatures of 6 to 9 degrees with light variable winds backing southeasterly.
Thursday will start off dry with bright or sunny spells in the east. Cloudier further west with rain developing in the west and northwest by early afternoon and then spreading southwards through the rest of the day. Highest temperatures of 15 to 19 degrees with fresh, gusty southerly winds.
On Thursday night, rain will continue for a time and will clear to the east overnight. Lowest temperatures of 10 to 13 degrees with winds becoming southwesterly and easing as rain clears.
Friday will be mainly dry with bright or sunny spells and perhaps a few showers. Highest temperatures of 15 to 18 degrees with moderate to fresh west to southwest winds.
Next weekend looks like it will be unsettled with rain or showers at times and with temperatures in the mid to high teens.
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.