Saskatchewan's Water Security Agency says there could be flooding if a predicted storm soaks a large part of the southern part of the province this weekend.

The agency says 50 to 80 millimetres of rain is possible in regions southeast of a line from Val Marie, Assiniboia, Regina and down to Estevan.

Most of the rainfall is expected on Saturday and Sunday.

The agency says the good news is that the Rafferty and Alameda reservoirs have flood storage space.

Torrential rain and flash floods in late June prompted more than 100 communities in Saskatchewan and Manitoba to declare a state of emergency.

The water security agency says many of those areas still have above-normal water levels and additional rainfall could lead to more localized flooding.