Manitoba Issues Overland Flood Watch Amid Heavy Rain Forecasts

The Government of Manitoba has issued an overland flood watch for parts of western and northwestern regions of the province ahead of a multi-day period of forecasted heavy rain. The provincial hydrologic forecast centre announced the alert on Friday, citing high probabilities of significant precipitation beginning Saturday and lasting through to Tuesday.

According to provincial statements, there remains uncertainty regarding the precise timing, intensity, and total amount of rainfall expected. Nonetheless, forecast models indicate a high likelihood that areas of western Manitoba, including the Parkland and northern regions, as well as the Saskatchewan and Assiniboine River basins in Saskatchewan, could receive more than 60 millimetres of rain during this period. Some forecast models suggest that thunderstorms could result in localized rainfall amounts exceeding 80 millimetres.

Most other parts of southern, southwestern, and central Manitoba, including the Interlake area, are expected to receive between 40 and 60 millimetres of precipitation. The Manitoba Emergency Management Organization has underlined that these rainfall amounts could lead to localized overland flooding, particularly in low-lying areas, regions with poor drainage, and locations that have recently experienced substantial rainfall from earlier storms this month.

Overland flooding occurs when the rate of surface runoff from high-intensity rainfall surpasses the capacity of ditches, drains, and natural waterways, causing water to flow across land rather than being absorbed or channelled away. This runoff can also lead to increased flows and elevated water levels in rivers, streams, and drainage systems.

The Assiniboine River, specifically the stretch from Shellmouth Dam to Brandon, remains under a flood warning. Additional high water advisories are still in effect for Lake of the Prairies, Swan Lake, Red Deer Lake, and the Red Deer River near its mouth at Highway 10. These advisories reflect ongoing concerns about water levels in key waterways following earlier precipitation events.

Earlier in the month, heavy rainfall resulted in significant overland flooding in several communities and farm fields in western and southern Manitoba, as well as the Interlake region. In response, the provincial government established a disaster financial assistance program to support affected areas.

The Manitoba Emergency Management Organization is continuing its coordination with local authorities, First Nations, and emergency management partners. The province has indicated that this collaboration includes reviewing existing emergency plans, sharing current information, and preparing resources for flood response and recovery. The hydrologic forecast centre will continue to monitor weather forecasts, river conditions, and precipitation trends, and will provide updated flood information as conditions evolve.

Weather forecasters predict that temperatures in southern Manitoba will approach seasonal averages through the afternoon, with an additional risk of isolated thundershowers. This meteorological outlook supports the provincial advisories concerning potential localized flooding due to the anticipated rainfall and storm activity.

While the timeframe of the rainfall event is projected from Saturday to Tuesday, the province has acknowledged that there could be considerable local variation in both intensity and total precipitation. Areas previously affected by rainfall this month remain particularly vulnerable due to saturated ground conditions and limited drainage capacity.

The flood watch and weather warnings have been issued in accordance with observed hydrologic conditions and forecasted precipitation, as determined by the province’s hydrologic forecast centre. The combination of antecedent wet conditions and the forecasted rainfall is expected to challenge existing flood mitigation infrastructure, particularly in areas with known drainage limitations.

The provincial government has communicated that it will continue to provide guidance and support for both immediate response and longer-term recovery efforts, working with a range of partners to ensure preparedness. The established disaster financial assistance program is among the measures designed to address impacts from flooding in affected communities.

The current advisories and watches are part of an ongoing process of monitoring and response in Manitoba, reflecting the province’s approach to flood risk management and emergency preparedness. The situation is subject to change based on actual rainfall amounts, storm development, and evolving hydrologic conditions. Further updates are anticipated as new information becomes available.