Saudi Arabia weather: Warnings of thunderstorms and flash floods for 5 days

The General Directorate of Civil Defense and the National Center for Meteorology in the Kingdom of Saudi Arabia issued advanced warnings regarding a comprehensive rainy weather system that will last for five days, as large areas of the Kingdom are expected to witness thunderstorms ranging in intensity from moderate to heavy, accompanied by active winds and hail showers, which increases the likelihood of flash floods in valleys and ravines.

Rainfall map and affected areas

The General Directorate of Civil Defense urged citizens and residents to exercise extreme caution and stay away from low-lying areas and flood channels. It explained that the rainy weather, which will continue until next Tuesday, will affect multiple regions with varying degrees of impact

• Makkah Region: Moderate to heavy rains may lead to flash floods, including Taif, Maysan, Adham, the Holy Capital, Turbah, Al-Muwayh, Al-Khurmah, and Ranyah.
• Riyadh region: will be affected by moderate to heavy rain with downdrafts that will stir up dust and sand, including the capital Riyadh, Al-Kharj, Al-Majma’ah, Al-Zulfi, Al-Ghat, Shaqra, Al-Dawadmi, Afif, Al-Quwai’iyah, and Wadi Al-Dawasir.
• Other regions: Al-Qassim, Hail, Madinah, the Northern Borders, Al-Jawf, the Eastern Province, Al-Baha, Asir, Jazan, and Najran will experience varying intensities of rain, with the possibility of flash floods and hail. Tabuk will be affected by light to moderate rain.

The climatic context of the rainfall event

This rainfall occurs during the "Wasam" season, which extends from mid-October to early December and is known as a transitional period characterized by sharp weather fluctuations in the Arabian Peninsula. During this period, the convergence of cold air masses from the north with warm, humid air currents from the Arabian Sea and the Red Sea leads to the formation of dense cumulonimbus clouds. The Wasam rains are known for their positive impact on the germination of desert plants and truffles, making it a vital period for the desert environment in the Kingdom.

Importance and expected effects

Despite the significant benefits of these rains in replenishing groundwater reservoirs and supporting the agricultural sector, they pose a major challenge in both urban and desert areas. The Kingdom's topography, which includes numerous dry valleys (wadis), makes it susceptible to flash floods that can form with tremendous speed. Government agencies, primarily the Civil Defense and the Ministry of Environment, Water and Agriculture, are working to strengthen infrastructure by constructing dams and flood drainage networks to mitigate these risks and harvest rainwater.

Public safety guidelines

The Civil Defense stressed the need to adhere to the instructions announced through various media outlets and social media platforms to ensure everyone's safety, emphasizing the importance of:

• Stay in safe places and do not go out except when absolutely necessary during heavy rainfall.
• Do not risk crossing valleys or water pools during flash floods.
• Stay away from electrical sources and metal objects in open areas during thunderstorms.
• Continuously monitor the alerts issued by the National Center for Meteorology.