Madagascar: Adverse weather forecast across most of the country through at least Jan. 26.

Thunderstorms and heavy rain are forecast across most of Madagascar through at least Jan. 27. Thunderstorms are likely across most of the island Jan. 24 before persisting over the northern half of the island Jan. 25-26. As of early Jan. 24, the Madagascar General Directorate of Meteorology has issued the following warnings:

• Red rain warnings (the highest level on a three-tier scale): Sofia and Diana regions. 4-12 cm (1.5-5 inches) of rainfall is forecast.

• Red strong swell warnings: Northwestern coast of Madagascar.

• Red strong wind warnings: Northern coast of Madagascar.

• Yellow rain warnings: Sava, Boeny, Betsiboka, and Analanjirofo regions.

• Yellow strong swell and strong wind warnings: Southwestern coast of Madagascar.

• Green rain warnings: Most of the rest of central Madagascar.

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 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. Disruptions to electricity and telecommunications services are possible where significant flooding, strong winds, or landslides impact utility networks.

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 the affected regions. Flooding could block regional rail lines; freight and passenger train delays and cancellations are possible 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 and some employees' inability to reach work sites.