
Calgary is under a rainfall warning, and although the forecasted moisture amounts are less than initial estimates, it is still set to be a very wet weekend in the city.
Environment and Climate Change Canada (ECCC) sayds heavy rain will bring 40 to 80 milimetres by Saturday evening.
Scattered showers are expected to start Friday afternoon before organizing into heavy rain in the evening.
Heavy rain is expected to continue through the day Saturday before tapering off in the evening.
ECCC is warning that heavy downpours can cause flash floods and water pooling on roads. Localized flooding in low-lying areas is also possible.
Downgraded forecast
A special weather statement was issued by the weather agency on Thursday, warning of 80 to 100 milimetres of rain in a 48-hour window starting Friday.
That has since been vacated in favour of a rainfall warning, but regardless of the exact measurements, the city will see significant rainfall.
The rain could provide some much-needed support to parts of southern Alberta, according to Marianna Greenhough with ECCC.
“In a lot of ways this rain is going to be somewhat welcome because it’s going to help replenish those reservoirs that are definitely a little low,” she said. “It’s a pretty significant event, so it’s definitely important to be prepared and be aware of what’s going on around you.”
The provincial drought map shows much of southeast and southwest Alberta under a severe drought.
Despite a need for moisture, this incoming system could be more that what people bargained for.
The Bow and Elbow Rivers could also swell this weekend, but the city isn’t expecting an flooding, thanks to all of its mitigation efforts.
Still, Calgarians should exercise caution and remain safe around the river.
Here are some tips from the city:
- Exercise caution around riverbanks as fast-moving water can cause erosion and destabilization.
- Warn children about the dangers of fast-moving water, especially those who live near rivers.
- Keep off temporarily closed pathways and away from any low-lying flooded areas near the river, for safety.
- Check for a boating advisory before going on the river and stay off the river if there is an advisory in place. Visit calgary.ca/riversafety for more information.
- Keep pets away from fast-moving water.
- Remove lawn furniture and other portable items off the riverbank.
- Secure items on your property in case of high winds or hail.
- Direct eavestroughs and extensions onto landscaped areas at least 1.5 metres (5 feet) away from your home and your neighbours’ home.
- For the safety of pathway users, the city says it may temporarily close some pathways dur to high flow rates on the Bow and Elbow.
In preparation for the rain, the city will be releasing some water downstream from the Glenmore Reservoir to make room.
“While precipitation is welcome due to recent dry conditions, the intensity and widespread nature of the expected rain is prompting precautionary action,” said Frank Frigo, Manager of Environmental Management for The City of Calgary. “Calgarians will notice water levels in the Glenmore Reservoir decreasing and flows in the Bow and Elbow River increasing. Although significant river flooding is not expected in Calgary, we are preparing for higher than forecasted conditions.”
High streamflow and rainfall advisories may be issued by the Provincial River Forecast Centre and Environment Canada in the coming days, the city adds.
Reporting pooled water on streets
The city says it has special devices in storm drains that allow the water to drain slowly and not overload the stormwater system.
If Calgarians see water pooling around storm drains, they should wait 90 mins and if it’s still not draining, take a photo and submit it via the 311 app or online request. The city says this will help crews respond on a priority basis.