What are the specific reasons for the suspension of schools in many parts of Saudi Arabia?

On June 19, the Saudi government announced that schools in many areas were closed due to strong storms, calling on people not to go out unless necessary.

Details are as follows:

Riyadh newspaper in Saudi Arabia reported that the weather changed suddenly, many areas were being hit by strong storms, and schools in many areas had been closed. Relevant government departments have issued a safety warning that there will be thunderstorms in the future, asking people to avoid going out as much as possible. According to the report, the Education Bureau of Dongfang Province 19 issued a notice saying that all schools in the district will be closed from the 20th.

Riyadh, the capital of Saudi Arabia, said in the morning that the capital region was hit by a strong storm, which led to dust all over the sky and extremely low visibility. Then there was a thunderstorm, and it is expected that the bad weather will last for several days. He appealed to people not to go out and stay at home.

It is reported that this severe storm hit a wide area, including nine provinces: Mecca, Medina, Tabuk, Zhufu, the northern border, Wheeler, Kassem, Riyadh and the east. No casualties were reported.