The Met Office has issued a yellow alert, warning that thunderstorms, probably accompanied by hail are expected to affect the area today.
Locally, the accumulated precipitation may exceed 35 millimetres per hour, it added.
The alert is in force from 12 noon to 6 pm today.
Be aware that thunderstorms may occur. Take extra care in exposed areas, like mountains, forest and open terrain. Disruption to outdoor activities is possible, the Met Office said.