Canada: Severe weather forecast over parts of northern Manitoba through early Sept. 21 /update 1

Heavy rainfall is forecast across parts of northern Manitoba through early Sept. 21. A low-pressure system is expected to stall over the area Sept. 20, producing rainfall totals of 4-6 cm (1.6-2.4 inches) over the areas through early Sept. 21. As of early Sept. 20, Environment Canada has issued red a red heavy rainfall warning (the highest level on a three-tier scale) for Tadoule Lake forecast district. Authorities may issue new alerts or update/rescind existing advisories as weather conditions change over the coming hours.

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 areas, especially where heavy rain has saturated the soil.

The severe weather could contribute to transport disruptions throughout the region. Floodwaters and debris flows may render some bridges or roadways impassable, impacting overland travel in and around affected areas. Ponding on road surfaces could cause hazardous driving conditions. Authorities could temporarily close some low-lying routes that become inundated by floodwaters.

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