The weather on Friday is expected to be mostly clear with some low cloud cover in coastal areas, the met office said.
In the afternoon, isolated storms are expected in the mountains and some areas inland.
The temperature is expected to rise to 39 degrees Celsius inland, 33 on the west coast, 35 on the rest of the coasts, and 30 in the mountains.
In the evening the weather is expected to be mostly clear, with temperatures set to fall to 25 degrees inland, 24 on the coast, and 18 in the mountains.
Some fog is expected on Saturday morning, with isolated storms expected throughout the weekend.
