The dead included three young Saudi men in Bisha, two others in Baha and two expatriates who were struck by a thunderbolt in Qunfudah.
Torrential floods also destroyed a number of houses, blocked roads and overturned vehicles. The rain and floods in the last few days uncovered the ineffective drainage systems in many parts of the country.
The two expatriates were killed by a thunderbolt, which also injured two of their companions in Qunfudah governorate in Makkah province. Civil Defense teams rushed the victims to hospital.
The rain inundated various parts of Qunfudah governorate and washed away large sections of the International Road linking Jeddah and Jazan.
Heavy rain lashed Bisha for more than three hours. Three people were killed and two others injured in a traffic accident in the city.