JEDDAH — Red alerts for heavy rain have been issued across parts of Jazan, Asir, Al-Baha and Makkah on Sunday, as moderate to heavy thunderstorms are forecast across several Saudi regions, according to the National Center for Meteorology (NCM). The red alerts cover parts of the four regions, with heavy rainfall expected in the affected areas. The thunderstorms are capable of causing flash floods According to the NCM's Sunday forecast, moderate to heavy thunderstorms capable of causing flash floods, accompanied by hail and active winds stirring up dust and sand, are expected over parts of Jazan, Asir, Al-Baha and Makkah. Fog may also form over parts of these regions, as well as coastal parts of the Eastern Province. For temperatures, Dammam is forecast to record the highest temperature at 42°C, followed by Makkah at 39°C, and Riyadh and Buraidah at 38°C. Madinah is expected to reach 37°C, followed by Jeddah and Jazan at 36°C, Hail at 33°C, Arar, Sakaka and Najran at 32°C, Tabuk at 28°C, Abha at 25°C and Al-Baha at 24°C. Humidity is forecast to reach 90 percent in Abha, Al-Baha and Jazan, followed by 85 percent in Jeddah and Dammam, and 80 percent in Makkah. Humidity levels are expected to reach 70 percent in Tabuk, Arar and Sakaka, 55 percent in Madinah and Hail, 35 percent in Riyadh and Najran, and 30 percent in Buraidah.