Port Arthur beach
Sun-worshippers will be in their element tomorrow with temperatures set to peak at a sweltering 25 degrees, according to a spokesperson from Met Éireann.
People are expected to head to beaches across the county in their droves as temperatures begin to heat up.
A spokesperson for Met Éireann said that temperatures on Thursday and Friday will be very good.
He said: "The best day of this spell will be tomorrow (Thursday). Donegal could be getting very warm with temperatures expected to be as high as 25 degrees. Tomorrow evening will be very warm."
He added that temperatures on Friday will be as high as 23 degrees.
However, the good spell of weather is expected to change on Friday night when thunder is forecast.
Saturday morning will begin with rain and Sunday will be fresh and cool.