A strong storm system over central Minnesota has given 20 to 40 millimetres (0.8 to 1.6 inches) of rain to much of southern Manitoba since yesterday afternoon. Environment Canada expects rainfall amounts from now to tomorrow night to range from 20 to 40 mm (0.8 to 1.6 inches) over the Portage la Prairie, Morden and Ste. Rose regions.
From 10 to 15 centimetres (four to six in.) of snowfall is expected in most areas west of the Manitoba escarpment and up to 25 cm (9.8 in.) over the higher elevations of the Riding, Duck, and Turtle mountains. This storm is accompanied by northerly winds that could gust up to 80 to 90 kilometres per hour (50 to 56 miles per hour) commencing this evening and continuing through to tomorrow afternoon.
Manitoba Water Stewardship advises that water levels and flows are increasing and expected to continue rising in most of the rivers and creeks within western and southern Manitoba. This includes the Red, Assiniboine, Pembina, Swan and Little Saskatchewan rivers and some of their tributaries. However, run-off waters should be contained within riverbanks as levels were relatively low before the storm started. Some of the rivers flowing into Lake Manitoba from the western side are also rising.
The level of Lake Winnipeg is 715.3 feet (218 metres) without wind effects. Wind set-up in the south basin could be as high as 1.2 m (four feet) with wave heights in the order of 1.2 m (four ft.) depending on shoreline slopes. The level of Lake Manitoba without wind effects is presently near 247.6 m (812.2 ft.). It is likely that lake levels would rise an additional 0.5 to 0.6 m p4 (1.5 to two ft.) due to wind set-up and wave heights in the 0.9 m (three ft.) range.
The Hydrologic Forecast Centre will monitor weather conditions and provide further updates as conditions change.
