Environment Canada says southern Saskatchewan can expect unsettled weather for most of the day.
John Paul Cragg at the weather office says the Regina area can expect thunderstorms dumping 25 to 40 millimeters of rain Wednesday and early Thursday.
Cragg says rainfall in some local areas could reach 75 millimeters or 3 inches.
Cragg adds a tornado watch has been issued for the eastern part of Saskatchewan near Yorkton, Moosomin and Carlyle for Wednesday afternoon.
He says a low pressure system is creating the unsettled weather and the chance of a tornado is higher in southwest Manitoba.