A rainfall warning is now in effect for southeast Saskatchewan, with Environment and Climate Change Canada forecasting significant rainfall totals through Thursday and into early Friday.
“We’re looking at a Colorado low system that’s coming up from the southwest,” said Stephen Berg, meteorologist with Environment and Climate Change Canada. “It’s bringing some heavy convective showers to the southeastern part of Saskatchewan over the next day, day and a half or so, and [there’s a] possibility of up to somewhere around 50 to 80 millimetres of rain over the next 36 hours or so.”
The expected amount of rainfall, equivalent to nearly three inches, could lead to water pooling in low-lying areas and overwhelm drainage systems in some communities.
“Make sure that… any stuff that'll collect water, make sure that it's kind of overturned,” Berg advised. “Make sure that people are aware and hopefully monitoring their basements, just in case there's issues with sewer backups or whatever… low-lying areas might be more susceptible to some overland flooding from some heavier bursts of rain.”
Berg also noted that the dry, compacted soil from the recent heat wave could make it harder for the ground to absorb rain efficiently. “It might be a bit difficult to absorb some of the rain as well if the ground has been, I guess, baked as it was earlier in the week with the really warm temperatures.”
Drivers are also urged to exercise caution on highways and rural roads.
“Roadways might be pretty soaked, so try to avoid driving on submerged parts of roadways… you might end up hydroplaning,” he said. “It'd be quite treacherous driving if they're on some flooded roadways.”
While parts of Saskatchewan, including Weyburn, saw temperatures in the mid-30s just days ago, the forecast for the long weekend is much cooler.
“Temperatures about anywhere from about 8 to about 14 degrees below normal values for the daytime highs,” Berg explained. “Might end up with temperatures below zero Friday night and Saturday night in the southeast as well, so that'll be something to keep in mind.”
That said, the earlier forecasted risk of snow for the May long weekend has dropped out of the picture.
“It looks like the rain might be ended before the temperatures dip down below zero, so it doesn't look like that'll be an issue for southeastern Saskatchewan,” said Berg. “There might be some icy surfaces with the cool down if there's still some standing water… so drivers should be really careful on that.”
The current system and cold snap will linger into the start of the week, but more seasonal conditions are expected to start returning after the holiday Monday.