Met Éireann has issued a status orange weather warning alert for this afternoon.
Heavy downpours and widespread showers are expected during the course of the afternoon and evening.
The national forecaster has also warned of localised spot flooding across the county.
A status yellow weather warning alert has also been issued for Donegal.
Highest temperatures of 18 to 20 degrees.
Subscribe or register today to discover more from DonegalLive.ie
Buy the e-paper of the Donegal Democrat, Donegal People's Press, Donegal Post and Inish Times here for instant access to Donegal's premier news titles.
Keep up with the latest news from Donegal with our daily newsletter featuring the most important stories of the day delivered to your inbox every evening at 5pm.