Algeria, Morocco: Adverse weather forecast across parts of the region through at least Sept. 4

Heavy rainfall and thunderstorms are forecast across most of Algeria and Morocco through at least Sept. 4. Daily rainfall totals of up to 4 cm (1.6 inches) are possible across parts of the affected area. Strong wind gusts, lightning, and hail may accompany storms.

As of early Sept. 4, the meteorological agencies have issued the following warnings:

• Orange heavy rainfall warnings (the middle level on a three-tier scale): Ain Guezzam, Bordj Badji Mokhtar, Djanet, and Tamanrasset provinces in southern Algeria

• Orange thunderstorm and strong wind warnings: Beni Mellal-Khenifra, northwestern and western Draa-Tafilalet, southern Fes-Meknes, southeastern Marrakech-Safi, and southern L'Oriental regions in Morocco

• Yellow heavy rainfall, thunderstorm, and strong wind warnings: Across the rest of the affected area.

Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming days.

Sustained heavy rainfall could trigger flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed stormwater drainage systems. Sites located downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides are possible in hilly or mountainous areas, especially where heavy rain has saturated the soil.

Authorities could issue mandatory evacuation orders for flood-prone communities over the coming days. Disruptions to electricity and telecommunications services are possible where significant flooding or landslides impact utility networks.

Due to the region's arid nature and poor stormwater management in some urban areas, even minor rainfall accumulations could quickly result in episodes of flash flooding. Flooding is possible in streams and wadis (dry riverbeds). Significant rainfall may be preceded by moderate winds and dust storms, though some areas - particularly desert areas - may experience high levels of dust without rain.

Floodwaters and debris flows may render some bridges, rail networks, or roadways impassable, impacting overland travel in and around affected areas. Ponding on road surfaces could cause hazardous driving conditions on regional highways. Authorities could temporarily close some low-lying routes that become inundated by floodwaters. Severe weather could also trigger flight delays and cancellations at airports in affected regions. Flooding could block regional rail lines; freight and passenger train delays and cancellations are likely in areas with heavy rainfall and potential track inundation.

Localized business disruptions may occur in low-lying areas; some businesses might not operate at full capacity because of flood damage to facilities, possible evacuations, and some employees' inability to reach work sites.