A snowfall warning is in effect across Ottawa with “significant” snowfall expected to start late Wednesday afternoon and continue until Thursday afternoon.

A “Texas low” is expected to bring snow totalling 15 to 20 cm, Environment and Climate Change Canada said. Potential hazards include reduced visibility in heavy snow as the fast-falling flakes make travel difficult. Isolated power outages are possible.

“Prepare for quickly changing and deteriorating travel conditions,” the weather agency warned, adding there may be a significant impact on rush hour traffic in the city.

“Take frequent breaks and avoid strain when clearing snow.”

Wednesday’s forecast is mainly cloudy before the snow begins late in the afternoon. The expected high is -8 C with a wind chill of -13 in the afternoon thanks to an east wind at 20 km/h.

Snow, at times heavy, is predicted to add up to 10 to 15 cm Wednesday night with an east wind at 20 km/h gusting to 40. The temperature is expected to rise to -5 C overnight but bundle up for a wind chill of -17 in the evening.

Another five cm of snow is forecast for Thursday before the snow winds down late in the afternoon. The temperature is expected to hold steady near -4 C. The predicted low is -15 C.

Friday’s forecast is for sunny skies and a high of -5 C. There’s a 60 per cent chance of flurries Friday night with an expected low of -6 C.