Algeria, Tunisia: Adverse weather forecast across parts of both countries through at least April 13

Heavy rainfall and thunderstorms are forecast across much of Algeria and Tunsiia through at least April 13. Daily rainfall totals of 2-6 cm (0.8-2.4 inches) are possible across the worst affected parts of the region and the heavy downpours may trigger flooding in low-lying areas. Strong wind gusts, lightning, and hail may accompany storms. Strong winds may generate dust storms in arid parts of the region.

As of April 12, the respective meteorological agencies have issued the following warnings:

• Red heavy rainfall warnings (the highest level on a three-tier scale): El M'ghair, El Oued, northern Ouargla, and Touggourt provinces in Algeria.

• Orange heavy rainfall warnings: Eastern Batna, Biskra, southern Djelfa, northern El Meniaa, Ghardaia, Khernchela, southern Laghouat, Ouled Djellal, Oum El Bouaghi, and Tebessa provinces in Algeria and Gabes, Kebili, Tataouine, and Tozeur governorates in Tunisia.

• Yellow heavy rainfall warnings: Coastal and adjacent inland areas of northeastern Algeria.

• Yellow thunderstorm warnings: Across eastern and northeastern Algeria and central and southeastern Tunisia.

• Yellow strong wind warnings: Across parts of central, northeastern, and western Algeria.

• Yellow dust storm warnings: Across parts of north-central and western Algeria.

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 the soil has become saturated by heavy rainfall.

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 arid nature of the region 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.