Ottawa residents planning a weekend getaway up the Ottawa Valley may want to pack an umbrella — and maybe rethink the itinerary altogether. Environment Canada has issued a rainfall warning for the Pembroke area, about 150 kilometres northwest of Ottawa, with showers and thunderstorms expected to roll through on Saturday.
What's in the forecast
Environment Canada is calling for between 50 and 80 millimetres of rain in some parts of the Pembroke region — a significant amount that could fall in a relatively short window if thunderstorms are involved. That kind of rainfall total is enough to trigger localized flooding on roads, in low-lying areas, and around storm drains that can't keep pace with the volume.
Thunderstorms embedded within the system also raise the risk of brief but intense downpours, gusty winds, and the possibility of hail, so anyone in the affected area should be prepared for rapidly changing conditions throughout the day Saturday.
The Ottawa connection
While the warning is centred on Pembroke and the surrounding Renfrew County area, it's very much on the radar for Ottawa. The two communities sit along the same weather corridor in the Ottawa Valley, and systems that soak Pembroke often swing through or brush past the capital within hours. Ottawa residents with cottages, family, or weekend plans in the Pembroke, Renfrew, or Petawawa areas should factor the warning into their travel plans, since Highway 17 and other routes connecting Ottawa to the upper valley could see reduced visibility and standing water during the heaviest bursts.
Even if the core of the heavy rainfall stays northwest of the city, Ottawa itself often picks up spillover showers and thunderstorm activity from the same frontal system, so it's worth keeping an eye on the forecast through the weekend rather than assuming the city will stay dry.
Staying safe this weekend
Environment Canada advises that people in or travelling through warned areas watch for rapidly rising water levels in streams, creeks, and ditches, and avoid walking or driving through flooded roads — it only takes a small amount of moving water to sweep a vehicle off the road. Storm drains can become blocked by debris during heavy rain events, leading to localized ponding on streets and underpasses.
For Ottawa residents heading out to the valley, or those simply watching the skies from the city, it's a good idea to check the latest Environment Canada updates before setting out Saturday, allow extra travel time, and keep headlights on in reduced visibility. Campers and cottagers in the Pembroke area in particular should secure any loose outdoor items and have a plan in case of sudden thunderstorm activity.
Environment Canada notes that rainfall warnings can be updated as the system develops, so conditions and totals may shift as Saturday approaches. Residents across the region, including in Ottawa, are encouraged to monitor official alerts throughout the weekend.
Source: CBC Ottawa
