A slow moving trough of low pressure over SW Manitoba will feed a southerly flow of moist unsettled air over southern MB today and tonight resulting in widespread showers and embedded thunderstorms. The slow moving and persistent shower activity will result in locally heavy rain as showers and thunderstorms advect over the same area (an effect known as "training") . Showers and thunderstorms will be most frequent over eastern ND today where flood watches are in effect due to the potential for 50 to 75 mm of rain in some areas. This area of heavy rain is forecast to spread northward into the Red River valley this evening and tonight, with 25 mm or more possible in areas mainly south and west of Winnipeg (although Winnipeg may also see significant amounts if the rain area expands further north). Note that locally heavy downpours this morning produced 32 mm of rain in Snowflake, 66 mm in Manitou, and 62 mm near Miami so a repeat performance is possible again tonight in some areas of the Red River valley.